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Pugesek, G., Müller, U., Williams, N.M., & Crone, E.E. Resurrecting historical observations to characterize species-specific nesting traits of bumblebees. American Naturalist.

Nicholson, C.C., Lonsdorf, E.V., Andersson, G.K.S., Knapp, J.L., Svensson, G.P., Gönczi, M., Jonsson, O., de Miranda, J.R., Williams, N.M., & Rundlöf, M. Landscapes of risk: A comparative analysis of landscape metrics for the ecotoxicological assessment of pesticide risk to bees. Journal of Applied Ecology.

Müller, U., Bruninga‐Socolar, B., Brokaw, J., Cariveau, D.P., and Williams, N.M. Integrating perspectives on ecology, conservation value, and policy of bee pollinator seed mixes. Frontiers in Ecology and the Environment, e2715.

Rosenheim, J.A., Williams, N.M., Rapp, J.M., and Schreiber, S.J. A test of balanced fitness limitations theory: Pollen limitation in plants. Ecology and Evolution 14 (2).

Lonsdorf, E.V., Rundlöf, M., Nicholson, C.C., and Williams, N.M. A spatially explicit model of landscape pesticide exposure to bees: Development, exploration, and evaluation. Science of the Total Environment 908, 168146

Williams, N.M., Buderi, A., Rowe, L., and Ward, K. Wildflower plantings enhance nesting opportunities for soil‐nesting bees. Ecological Applications, e2935.


Page, M.L., and Williams, N.M. Evidence of exploitative competition between honey bees and native bees in two California landscapes. Journal of Animal Ecology 92 (9), 1802-1814.

Lundin, O., Boetzl, F.A., Ward, K.L., and Williams, N.M. 2023. Wildflower plantings have mixed effects on insect herbivores and their natural enemies. Agriculture, Ecosystems & Environment 355, 108587.

Williams, N.M. and Hemberger, J. 2023. Climate, pesticides, and landcover drive declines of the western bumble bee. Proceedings of the National Academy of Sciences 120:e2221692120.

Page, M.L. and Williams, N.M. 2023. Honey bee introductions displace native bees and decrease pollination of a native wildflower. Ecology 104:e3939.

Stuligross, C., Melone, G.G., Wang, L. and Williams, N.M. 2023. Sublethal behavioral impacts of resource limitation and insecticide exposure reinforce negative fitness outcomes for a solitary bee. Science of The Total Environment 867: 161392.

Wauters, V.M., Jarvis-Shean, K., Williams, N., Hodson, A., Hanson, B.D., Haring, S., Wilson, H., Westphal, A., Solis, S.S., Daane, K. and Mitchell, J. 2023. Developing cover crop systems for California almonds: Current knowledge and uncertainties. Journal of Soil and Water Conservation 78: 5A-11A.

Schaeffer, R.N., Crowder, D.W., Illán, J.G., Beck, J.J., Fukami, T., Williams, N.M. and Vannette, R.L. 2023. Disease management during bloom affects the floral microbiome but not pollination in a mass‐flowering crop. Journal of Applied Ecology 60: 64-76.

Rowe, G., Hagadorn, M.A., Lindsay, T.T.T., Malfi, R., Williams, N.M. and Strange, J.P. 2023. Production of bumblebees (Hymenoptera: Apidae) for pollination and research. In Mass Production of Beneficial Organisms (pp. 559-579). Academic Press.

Hemberger, J.A., Rosenberger, N.M. and Williams, N.M. 2023. Experimental heatwaves disrupt bumblebee foraging through direct heat effects and reduced nectar production. Functional Ecology 37:591-601.

Sardiñas, H.S., Ryals, R. and Williams, N.M. 2023. Carbon farming can enhance pollinator resources: Carbon farming can help protect bees and other wild pollinators that are essential to California agriculture. California Agriculture 76:104-110.


Genung, M.A., Reilly, J., Williams, N.M., Buderi, A., Gardner, J. and Winfree, R. 2022. Rare and declining bee species are key to consistent pollination of wildflowers and crops across large spatial scales. Ecology 104:e3899.

Lemanski, N.J., Williams, N.M., and Winfree, R. 2022. Greater bee diversity is needed to maintain crop pollination over time. Nature Ecology & Evolution 6:1516-1523.

Rundlöf, M., Stuligross, C., Lindh, A., Malfi, R.L., Burns, K., Cibotti, S., Mola, J.M., and Williams, N.M. 2022. Flower plantings support wild bee reproduction and may also mitigate pesticide exposure effects. Journal of Applied Ecology 59:2117-2127.

Fisher, K., Watrous, K.M., Williams, N.M., Richardson, L.L., and Woodard, S.H. 2022. A contemporary survey of bumble bee diversity across the state of California. Ecology and Evolution 12:e8505.

Allen-Perkins et al. 2022. CropPol: A dynamic, open and global database on crop pollination. Ecology 103:e3614.

Malfi, R.L., Crone, E., Rundlöf, M., and Williams, N.M. 2022. Early resources lead to persistent benefits for bumble bee colony dynamics. Ecology 103:e03560.


Stuligross, C. and Williams, N.M. 2021. Past insecticide exposure reduces bee reproduction and population growth rate. Proceedings of the National Academy of Sciences 118:e2109909118.

Page, M.L., Nicholson, C.C., Brennan, R.M., Britzman, A.T., Greer, J., Hemberger, J., Kahl, H., Müller, U., Peng, Y., Rosenberger, N.M., Stuligross, C., Wang, L., Yang, L.H., and Williams, N.M. 2021. A meta-analysis of single visit pollination effectiveness comparing honeybees and other floral visitors. American Journal of Botany 108:1-12.

Nicholson, C.C. and Williams, N.M. 2021. Cropland heterogeneity drives frequency and intensity of pesticide use. Environmental Research Letters 16:074008.

Lundin, O., Rundlöf, M., Jonsson, M., Bommarco, R., and Williams, N.M. 2021. Integrated pest and pollinator management–expanding the concept. Frontiers in Ecology and the Environment 19:283-291.

Mola, J.M., Stuligross, C., Page, M.L., Rutkowski, D., and Williams, N.M. 2021. Impact of “non-lethal” tarsal clipping on bumble bees (Bombus vosnesenskii) may depend on queen stage and worker size. Journal of Insect Conservation 25:195-201.

Kerr, N., Malfi, R.L., Williams, N.M., and Crone, E. 2021. Larger workers outperform smaller workers across resource environments: An evaluation of demographic data using functional linear models. Ecology and Evolution 11:2814-2827.


Woodard, S.H. et al. 2020. Towards a US national program for monitoring native bees. Biological Conservation 252:108821.

Albrecht, M., Kleijn, D., Williams, N.M. et al. 2020. The effectiveness of flower strips and hedgerows on pest control, pollination services and crop yield: a quantitative synthesis. Ecology Letters 23:1488-1498.

Stuligross, C. and Williams, N.M. 2020. Pesticide and resource stressors additively impair wild bee reproduction. Proceedings of the Royal Society B 287:20201390.

Reilly, J.R. et al. 2020. Crop production in the USA is frequently limited by a lack of pollinators. Proceedings of the Royal Society B: 287:20200922.

Mola, J.M., Miller, M.R., O’Rourke, S.M., and Williams, N.M. 2020. Wildfire reveals transient changes to individual traits and population responses of a native bumble bee (Bombus vosnesenskii). Journal of Animal Ecology 89:1799-1810.

Boyle, N.K., Artz, D.R., Lundin, O., Ward, K., Picklum, D., Wardell, G.I., Williams, N.M., Pitts-Singer, T.L. 2020. Wildflower plantings promote blue orchard bee, Osmia lignaria (Hymenoptera: Megachilidae), reproduction in California almond orchards. Ecology and Evolution 10:3189-3199.

Mola, J.M., Miller, M.R., O’Rourke, S.M., and Williams, N.M. 2020. Forests do not limit bumble bee foraging movements in a montane meadow complex. Ecological Entomology 45:955-965.

Nicholson, C.C., Ward, K.L., Williams, N.M., Isaacs, R., Mason, K.S., Wilson, J.K. 2020. Mismatched outcomes for biodiversity and ecosystem services: testing the responses of crop pollinators and wild bee biodiversity to habitat enhancement. Ecology Letters 23:326-335

LoPresti, E.F., Goidell, J., Mola, J.M., Page, M.L., Specht, C.D., Stuligross, C., Weber, M.G., Williams, N.M., & Karban, R. 2020. The lever action hypothesis for pendulous hummingbird flowers; experimental evidence from a columbine. Annals of Botany 125:59-65.


Malfi, R.L., Crone, E.E., Williams, N.M. 2019. Demographic benefits of early season resources for bumble bee (B. vosnesenskii) colonies. Oecologia 191: 377-388

Williams, N.M., Mola, J.M., Stuligross, C., Harrison, T., Page, M.L., Brennan, R.M., Rosenberger, N.M., & Rundlöf, M. 2019. Fantastic bees and where to find them: locating the cryptic overwintering queens for a western bumble bee. Ecosphere.

Mola, J.M. and Williams, N.M. 2019. A review of methods for the study of bumble bee movement. Apidologie 50:497-514.

Kerr, N.Z., Crone, E.E., and Williams, N.M. 2019. Integrating vital rates explains optimal worker size for resource return by bumblebee workers. Functional Ecology 33:467-478.

Lundin, O., Ward, K.L., and Williams, N.M. 2019. Identifying native plants for coordinated habitat management of arthropod pollinators, herbivores and natural enemies. Journal of Applied Ecology 56:665-676.

Sponsler, D.B., Grozinger, C. M., Hitaj, C., Rundlof, M., Botias, C., Code, A., Lonsdorf, E.V., Melathopoulos, A.P., Smith, D.J., Suryanarayanan, S., Thogmartin, W.G., Williams, N.M., Zhang, M., Douglas, M.R. 2019. Pesticides and pollinators: A socioecological synthesis. Science of the Total Environment 662:1012–1027.

Sgolastra, F., Hinarejos, S., Pitts-Singer, T.L., Boyle, N.K., Joseph, T., Lūckmann, J., Raine, N.W., Singh, R., Williams, N.M., Bosch, J. 2018. Pesticide Exposure Assessment Paradigm for Solitary Bees, Environmental Entomology 48:22–35.


Iles, D.T., N.M. Williams, and E.E. Crone. 2018. Source-sink dynamics of bumblebees in rapidly changing landscapes. Journal of Applied Ecology 55:2802–2811.

LoPresti, E.F., J.I. Van Wyk, J.M. Mola, K. Toll, T.J. Miller, and N.M. Williams. 2018. Effects of wildfire on floral display size and pollinator community reduce outcrossing rate in a plant with a mixed mating system. American Journal of Botany 105:1154–1164.

Saul-Gershenz, L., J.G. Millar, J.S. McElfresh, and N.M. Williams. 2018. Deceptive signals and behaviors of a cleptoparasitic beetle show local adaptation to different host bee species. Proceedings of the National Academy of Sciences 115:9756–9760.

Williams, N.M., and E.V. Lonsdorf. 2018. Selecting cost-effective plant mixes to support pollinators. Biological Conservation 217:195–202.

Winfree, R., J.R. Reilly, I. Bartomeus, D.P. Cariveau, N.M. Williams, and J. Gibbs. 2018. Species turnover promotes the importance of bee diversity for crop pollination at regional scales. Science 359:791–793.

Mola, J.M., and N.M. Williams. 2018. Fire-induced change in floral abundance, density, and phenology benefits bumble bee foragers. Ecosphere 9.

Parker, A.J., N.M. Williams, and J.D. Thomson. 2018. Geographic patterns and pollination ecotypes in Claytonia virginica. Evolution 72:215-216.


Lichtenberg, E.M., Kennedy, C.M., Kremen, C., Batáry, P., Berendse, F., Bommarco, R., Bosque‐Pérez, N.A., Carvalheiro, L.G., Snyder, W.E., Williams, N.M. and Winfree, R., 2017. A global synthesis of the effects of diversified farming systems on arthropod diversity within fields and across agricultural landscapes. Global Change Biology.

Isaacs, R., Williams, N., Ellis, J., Pitts-Singer, T.L., Bommarco, R., & Vaughan, M. 2017. Integrated Crop Pollination: Combining strategies to ensure stable and sustainable yields of pollination-dependent crops. Basic and Applied Ecology 22:44-60.

Lundin, O., Ward, K.L., Artz, D.R., Boyle, N.K., Pitts-Singer, T.L., & Williams, N.M. 2017. Wildflower Plantings Do Not Compete With Neighboring Almond Orchards for Pollinator Visits. Environmental Entomology, 46(3), 559-564.

Genung, M.A., Fox, J., Williams, N.M., Kremen, C., Ascher, J. Gibbs, J. and R. Winfree. 2017 Pollinator abundance, rather than species richness, drives the temporal variability of pollination services. Ecology 98:1807-1816.

Schaeffer, R.N., Vannette, R.L., Brittain, C., Williams, N.M., & Fukami, T. 2017. Non‐target effects of fungicides on nectar‐inhabiting fungi of almond flowers. Environmental Microbiology Reports 9: 79-84.


M’Gonigle, L.K., N.M. Williams, E. Lonsdorf, and C. Kremen. 2016. A Tool for Selecting Plants When Restoring Habitat for Pollinators. Conservation Letters. PDF

Parker, A. J., N.M. Williams, and J.D. Thomson. 2016. Specialist pollinators deplete pollen in the spring ephemeral wildflower Claytonia virginica. Ecology and Evolution. PDF

Crone, E.E., and N.M. Williams. 2016. Bumble bee colony dynamics: quantifying the importance of land use and floral resources for colony growth and queen production. Ecology Letters. PDF

Rosenheim, J.A., S.J. Schreiber, and N.M. Williams. 2016. Does an “oversupply” of ovules cause pollen limitation? New Phytologist 210:324–332.

Ullmann, K.S., Meisner, M.H., and Williams, N.M. 2016. Impact of tillage on the crop pollinating, ground-nesting bee, Peponapis pruinosa in California. Agriculture, Ecosystems & Environment 232:240-246.

Koh, I., E.V. Lonsdorf, N.M. Williams, C. Brittain, R. Isaacs, J. Gibbs, and T.H. Ricketts. 2016. Modeling the status, trends, and impacts of wild bee abundance in the United States. Proceedings of the National Academy of Sciences 113:140–145. PDF

Rosenheim, J.A., N.M. Williams, S.J. Schreiber, and J.M. Rapp. 2016. Modest pollen limitation of lifetime seed production is in good agreement with modest uncertainty in whole-plant pollen receipt. American Naturalist. 187:397–404.


Gillespie, S., R. Long, and N.M. Williams. 2015. Indirect Effects of Field Management on Pollination Service and Seed Set in Hybrid Onion Seed Production. Journal of Economic Entomology 108 (6): 2511-2517

Williams, N.M., Ward, K.L., Pope, N., Isaacs, R. Wilson, J., May, E.A., Ellis, J., Daniels, J., Pence, A., Ullmann, and K. Peters, J. 2015. Native wildflower plantings support wild bee abundance and diversity in agricultural landscapes across the United States. Ecological Applications. PDF

Fründ, J., K.S. McCann, and N.M. Williams. 2015. Sampling bias is a challenge for quantifying specialization and network structure: lessons from a quantitative niche model. Oikos. Early-view PDF

Kleijn, D., Winfree, R., Bartomeus, I., Carvalheiro, L.G., Henry, M., Isaacs, R., Klein, A.M., Kremen, C., M’Gonigle, L.K., Rader, R., Ricketts, T.H., Williams, N.M., et al. (including K. L. Ward) 2015. Delivery of crop pollination services is an insufficient argument for wild pollinator conservation. Nature Communications 6:7414 PDF featured in The Washington Post, The Guardian, LA Times, The Independent, Wired, Quartz, Conservation Magazine and Science Daily

Forrest, J.R. K., R.W. Thorp, C. Kremen, and N.M. Williams. 2015. Contrasting patterns in species and functional-trait diversity of bees in an agricultural landscape. Journal of Applied Ecology 52:706–715. PDF

Winfree, R., J.W. Fox, N.M. Williams, J.R. Reilly, and D.P. Cariveau. 2015. Abundance of common species, not species richness, drives delivery of a real-world ecosystem service. Ecology Letters. PDF

Schreiber, S.J., J.A. Rosenheim, N.M. Williams, and L.D. Harder. 2015. Evolutionary and Ecological Consequences of Multiscale Variation in Pollen Receipt for Seed Production. The American Naturalist 185:E14–E29. PDF


Gillespie, S., R. Long, N. Seitz, and N.M. Williams. 2014. Insecticide Use in Hybrid Onion Seed Production Affects Pre- and Postpollination Processes. Journal of Economic Entomology 107:29–37.

Rosenheim, J.A., N.M. Williams, and S.J. Schreiber. 2014. Parental Optimism versus Parental Pessimism in Plants: How Common Should We Expect Pollen Limitation to Be? The American Naturalist 184:75–90. PDF

Wilkerson, M.L., K.L. Ward, N.M. Williams, K.S. Ullmann, and T.P. Young. 2014. Diminishing Returns from Higher Density Restoration Seedings Suggest Trade-offs in Pollinator Seed Mixes. Restoration Ecology 22:782–789. PDF

Winfree, R., N.M. Williams, J. Dushoff, and C. Kremen. 2014. Species Abundance, Not Diet Breadth, Drives the Persistence of the Most Linked Pollinators as Plant-Pollinator Networks Disassemble. The American Naturalist 183:600–611. PDF


Brittain, C., N.M. Williams, C. Kremen, and A.-M. Klein. 2013. Synergistic effects of non-Apis bees and honey bees for pollination services. Proceedings of the Royal Society B: Biological Sciences 280:20122767–20122767. PDF

Cariveau, D.P., N.M. Williams, F.E. Benjamin, and R. Winfree. 2013. Response diversity to land use occurs but does not consistently stabilise ecosystem services provided by native pollinators. Ecology Letters 16:903–911. PDF

Garibaldi, L.A., et al. 2013. Wild Pollinators Enhance Fruit Set of Crops Regardless of Honey Bee Abundance. Science 339:1608–1611. PDF

Kennedy, C. M., et al. 2013. A global quantitative synthesis of local and landscape effects on wild bee pollinators in agroecosystems. Ecology Letters 16:584–599. PDF

Minckley, R.L., T.H. Roulston, and N.M. Williams. 2013. Resource assurance predicts specialist and generalist bee activity in drought. Proceedings of the Royal Society of London B: Biological Sciences 280:20122703.

Williams, N.M., and R. Winfree. 2013. Local habitat characteristics but not landscape urbanization drive pollinator visitation and native plant pollination in forest remnants. Biological Conservation 160:10–18. PDF


Klein, A.-M., C. Brittain, S.D. Hendrix, R. Thorp, N.M. Williams, and C. Kremen. 2012. Wild pollination services to California almond rely on semi-natural habitat: Wild pollination services to California almond. Journal of Applied Ecology. PDF

Schleuning, M., et al. 2012. Specialization of Mutualistic Interaction Networks Decreases toward Tropical Latitudes. Current Biology 22:1925–1931. PDF

Williams, N M., J. Regetz, and C. Kremen. 2012. Landscape-scale resources promote colony growth but not reproductive performance of bumble bees. Ecology 93:1049–1058. PDF


Tomich, T. ., S. Brodt, H. Ferris, R. Galt, W R. Horwath, E. Kebreab, J.H. J. Leveau, D. Liptzin, M. Lubell, P. Merel, R. Michelmore, T. Rosenstock, K. Scow, J. Six, N.M. Williams, and L. Yang. 2011. Agroecology: A Review from a Global-Change Perspective. Annual Review of Environment and Resources 36:193–222. PDF

Golet, G. H., T. Gardali, J. W. Hunt, D. A. Koenig, and N.M. Williams. 2011. Temporal and Taxonomic Variability in Response of Fauna to Riparian Restoration. Restoration Ecology 19:126–135. PDF

Williams, N.M. 2011. Restoration of Nontarget Species: Bee Communities and Pollination Function in Riparian Forests. Restoration Ecology 19:450–459. PDF

Williams, N.M., D. Cariveau, R. Winfree, and C. Kremen. 2011. Bees in disturbed habitats use, but do not prefer, alien plants. Basic and Applied Ecology 12:332–341. PDF


Williams, N.M., E.E. Crone, T.H. Roulston, R. L. Minckley, L. Packer, and S.G. Potts. 2010. Ecological and life-history traits predict bee species responses to environmental disturbances. Biological Conservation 143:2280–2291. PDF


Lonsdorf, E., C. Kremen, T. Ricketts, R. Winfree, N. Williams, and S. Greenleaf. 2009. Modelling pollination services across agricultural landscapes. Annals of Botany 103:1589–1600.

Richards, S.A., N.M. Williams, and L.D. Harder. 2009. Variation in Pollination: Causes and Consequences for Plant Reproduction. The American Naturalist 174:382–398.


Elliott, S.E., R.E. Irwin, L.S. Adler, and N.M. Williams. 2008. The nectar alkaloid, gelsemine, does not affect offspring performance of a native solitary bee, Osmia lignaria (Megachilidae). Ecological Entomology 33:298–304.


Greenleaf, S.S., N.M. Williams, R. Winfree, and C. Kremen. 2007. Bee foraging ranges and their relationship to body size. Oecologia 153:589–596.

Kremen, C., N.M. Williams, M.A. Aizen, B. Gemmill-Herren, G. LeBuhn, R. Minckley, L. Packer, S.G. Potts, T.H. Roulston, I. Steffan-Dewenter, D.P. Vázquez, R. Winfree, L. Adams, E.E. Crone, S.S. Greenleaf, T.H. Keitt, A.-M. Klein, J. Regetz, and T.H. Ricketts. 2007. Pollination and other ecosystem services produced by mobile organisms: a conceptual framework for the effects of land-use change. Ecology Letters 10:299–314.

Vázquez, D.P., C.J. Melián, N.M. Williams, N. Blüthgen, B.R. Krasnov, and R. Poulin. 2007. Species abundance and asymmetric interaction strength in ecological networks. Oikos 116:1120–1127.

Williams, N.M., and C. Kremen. 2007. Resource distributions among habitats determine solitary bee offspring production in a mosaic landscape. Ecological Applications 17:910–921.

Winfree, R., N.M. Williams, J. Dushoff, and C. Kremen. 2007. Native bees provide insurance against ongoing honey bee losses. Ecology Letters 10:1105–1113.

Winfree, R., N.M. Williams, H. Gaines, J.S. Ascher, and C. Kremen. 2007. Wild bee pollinators provide the majority of crop visitation across land-use gradients in New Jersey and Pennsylvania, USA: Crop Visitation By Wild Pollinators. Journal of Applied Ecology 45:793–802.


Cane, J.H., R.L. Minckley, L.J. Kervin, T.H. Roulston, and N.M. Williams. 2006. Complex Responses Within A Desert Bee Guild (Hymenoptera: Apiformes) To Urban Habitat Fragmentation. Ecological Applications 16:632–644.

Kim, J., N.M. Williams, and C. Kremen. 2006. Effects of Cultivation and Proximity to Natural Habitat on Ground-nesting Native Bees in California Sunflower Fields. Journal of the Kansas Entomological Society 79:309–320.


Larsen, T.H., N.M. Williams, and C. Kremen. 2005. Extinction order and altered community structure rapidly disrupt ecosystem functioning. Ecology Letters 8:538–547.

Winfree, R., J. Dushoff, E.E. Crone, C.B. Schultz, R. V. Budny, N.M. Williams, and C. Kremen. 2005. Testing Simple Indices of Habitat Proximity. The American Naturalist 165:707–717.


Kremen, C., N.M. Williams, R.L. Bugg, J.P. Fay, and R.W. Thorp. 2004. The area requirements of an ecosystem service: crop pollination by native bee communities in California. Ecology Letters 7:1109–1119.


Williams, N.M. 2003. Use of novel pollen species by specialist and generalist solitary bees (Hymenoptera: Megachilidae). Oecologia 134:228–237.

Williams, N.M., and V.J. Tepedino. 2003. Consistent mixing of near and distant resources in foraging bouts by the solitary mason bee Osmia lignaria. Behavioral Ecology 14:141–149.


Kremen, C., N.M. Williams, and R.W. Thorp. 2002. Crop pollination from native bees at risk from agricultural intensification. Proceedings of the National Academy of Sciences 99:16812–16816.

2001 & Earlier

Williams, N.M., and K. Goodell. 2000. Association of Mandible Shape and Nesting Material in Osmia panzer (Hymenoptera: Megachilidae): a Morphometric Analysis. Annals of the Entomological Society of America 93:318–325.

Williams, N.M., and J.D. Thomson. 1998. Trapline foraging by bumble bees: III. Temporal patterns of visitation and foraging success at single plants. Behavioral Ecology 9:612–621.

Waser, N.M., L. Chittka, M.V. Price, N M. Williams, and J. Ollerton. 1996. Generalization in Pollination Systems, and Why it Matters. Ecology 77:1043–1060.

Jeanne, R. L., N.M. Williams, and B.S. Yandell. 1992. Age polyethism and defense in a tropical social wasp (Hymenoptera: Vespidae). Journal of Insect Behavior 5:211–227.