Wang, X.T., Y. Wang, A. Auderset, D.M. Sigman, H. Ren, A. Martínez-García, G.H. Haug, et al. 2022. “Oceanic Nutrient Rise and the Late Miocene Inception of Pacific Oxygen-Deficient Zones”. Proceedings of the National Academy of Sciences of the United States of America 119. doi:10.1073/pnas.2204986119.

Ren, H., D.M. Sigman, M.-T. Chen, and S.-J. Kao. 2012. “Elevated Foraminifera-Bound Nitrogen Isotopic Composition During the Last Ice Age in the South China Sea and Its Global and Regional Implications”. Global Biogeochemical Cycles 26. doi:10.1029/2010GB004020.

Ren, H., D.M. Sigman, R.C. Thunell, and M.G. Prokopenko. 2012. “Nitrogen Isotopic Composition of Planktonic Foraminifera from the Modern Ocean and Recent Sediments”. Limnology and Oceanography 57. American Society of Limnology and Oceanography Inc.: 1011-24. doi:10.4319/lo.2012.57.4.1011.

Meckler, A.N., H. Ren, D.M. Sigman, N. Gruber, B. Plessen, C.J. Schubert, and G.H. Haug. 2011. “Deglacial Nitrogen Isotope Changes in the Gulf of Mexico: Evidence from Bulk Sedimentary and Foraminifera-Bound Nitrogen in Orca Basin Sediments”. Paleoceanography 26. Blackwell Publishing Ltd. doi:10.1029/2011PA002156.

Ren, H., D.M. Sigman, A.N. Meckler, B. Plessen, R.S. Robinson, Y. Rosenthal, and G.H. Haug. 2009. “Foraminiferal Isotope Evidence of Reduced Nitrogen Fixation in the Ice Age Atlantic Ocean”. Science 323: 244-48. doi:10.1126/science.1165787.

Wang, X.T., D.M. Sigman, A.L. Cohen, D.J. Sinclair, R.M. Sherrell, M.A. Weigand, D.V. Erler, and H. Ren. 2015. “Isotopic Composition of Skeleton-Bound Organic Nitrogen in Reef-Building Symbiotic Corals: A New Method and Proxy Evaluation at Bermuda”. Geochimica Et Cosmochimica Acta 148. Elsevier Ltd: 179-90. doi:10.1016/j.gca.2014.09.017.

Wang, X.T., M.G. Prokopenko, D.M. Sigman, J.F. Adkins, L.F. Robinson, H. Ren, S. Oleynik, B. Williams, and G.H. Haug. 2014. “Isotopic Composition of Carbonate-Bound Organic Nitrogen in Deep-Sea Scleractinian Corals: A New Window into past Biogeochemical Change”. Earth and Planetary Science Letters 400. Elsevier: 243-50. doi:10.1016/j.epsl.2014.05.048.

Martínez-García, A., D.M. Sigman, H. Ren, R.F. Anderson, M. Straub, D.A. Hodell, S.L. Jaccard, T.I. Eglinton, and G.H. Haug. 2014. “Iron Fertilization of the Subantarctic Ocean During the Last Ice Age”. Science 343. American Association for the Advancement of Science: 1347-50. doi:10.1126/science.1246848.

Ren, H., B.G. Brunelle, D.M. Sigman, and R.S. Robinson. 2013. “Diagenetic Aluminum Uptake into Diatom Frustules and the Preservation of Diatom-Bound Organic Nitrogen”. Marine Chemistry 155: 92-101. doi:10.1016/j.marchem.2013.05.016.

Straub, M., D.M. Sigman, H. Ren, A. Martínez-García, A.N. Meckler, M.P. Hain, and G.H. Haug. 2013. “Changes in North Atlantic Nitrogen Fixation Controlled by Ocean Circulation”. Nature 501: 200-203. doi:10.1038/nature12397.

Straub, M., M.M. Tremblay, D.M. Sigman, A.S. Studer, H. Ren, J.R. Toggweiler, and G.H. Haug. 2013. “Nutrient Conditions in the Subpolar North Atlantic During the Last Glacial Period Reconstructed from Foraminifera-Bound Nitrogen Isotopes”. Paleoceanography 28. Blackwell Publishing Ltd: 79-90. doi:10.1002/palo.20013.

Ren, H., A.S. Studer, S. Serno, D.M. Sigman, G. Winckler, R.F. Anderson, S. Oleynik, R. Gersonde, and G.H. Haug. 2015. “Glacial-to-Interglacial Changes in Nitrate Supply and Consumption in the Subarctic North Pacific from Microfossil-Bound N Isotopes at Two Trophic Levels”. Paleoceanography 30. Blackwell Publishing Ltd: 1217-32. doi:10.1002/2014PA002765.

Studer, A.S., F. Mekik, H. Ren, M.P. Hain, S. Oleynik, A. Martínez-García, G.H. Haug, and D.M. Sigman. 2021. “Ice Age-Holocene Similarity of Foraminifera-Bound Nitrogen Isotope Ratios in the Eastern Equatorial Pacific”. Paleoceanography and Paleoclimatology 36. John Wiley and Sons Inc. doi:10.1029/2020PA004063.

Sigman, D.M., F. Fripiat, A.S. Studer, P.C. Kemeny, A. Martínez-García, M.P. Hain, X. Ai, X. Wang, H. Ren, and G.H. Haug. 2021. “The Southern Ocean During the Ice Ages: A Review of the Antarctic Surface Isolation Hypothesis, With Comparison to the North Pacific”. Quaternary Science Reviews 254. Elsevier Ltd. doi:10.1016/j.quascirev.2020.106732.

Zhang, R., X.T. Wang, H. Ren, J. Huang, M. Chen, and D.M. Sigman. 2020. “Dissolved Organic Nitrogen Cycling in the South China Sea From an Isotopic Perspective”. Global Biogeochemical Cycles 34. Blackwell Publishing Ltd. doi:10.1029/2020GB006551.

Smart, S.M., S.E. Fawcett, H. Ren, R. Schiebel, E.M. Tompkins, A. Martínez-García, L. Stirnimann, A. Roychoudhury, G.H. Haug, and D.M. Sigman. 2020. “The Nitrogen Isotopic Composition of Tissue and Shell-Bound Organic Matter of Planktic Foraminifera in Southern Ocean Surface Waters”. Geochemistry, Geophysics, Geosystems 21. Blackwell Publishing Ltd. doi:10.1029/2019GC008440.

Kast, E.R., D.A. Stolper, A. Auderset, J.A. Higgins, H. Ren, X.T. Wang, A. Martínez-García, G.H. Haug, and D.M. Sigman. 2019. “Nitrogen Isotope Evidence for Expanded Ocean Suboxia in the Early Cenozoic”. Science 364. American Association for the Advancement of Science: 386-89. doi:10.1126/science.aau5784.

Schiebel, R., S.M. Smart, A. Jentzen, L. Jonkers, R. Morard, J. Meilland, E. Michel, et al. 2018. “Advances in Planktonic Foraminifer Research: New Perspectives for Paleoceanography”. Revue De Micropaleontologie 61. Elsevier Masson SAS: 113-38. doi:10.1016/j.revmic.2018.10.001.

Wang, X.T., A.L. Cohen, V. Luu, H. Ren, Z. Su, G.H. Haug, and D.M. Sigman. 2018. “Natural Forcing of the North Atlantic Nitrogen Cycle in the Anthropocene”. Proceedings of the National Academy of Sciences of the United States of America 115. National Academy of Sciences: 10606-11. doi:10.1073/pnas.1801049115.

Smart, S.M., H. Ren, S.E. Fawcett, R. Schiebel, M. Conte, P.A. Rafter, K.K. Ellis, et al. 2018. “Ground-Truthing the Planktic Foraminifer-Bound Nitrogen Isotope Paleo-Proxy in the Sargasso Sea”. Geochimica Et Cosmochimica Acta 235. Elsevier Ltd: 463-82. doi:10.1016/j.gca.2018.05.023.

Ren, H., D.M. Sigman, A. Martínez-García, R.F. Anderson, M.-T. Chen, A.C. Ravelo, M. Straub, G.T.F. Wong, and G.H. Haug. 2017. “Impact of Glacial Interglacial Sea Level Change on the Ocean Nitrogen Cycle”. Proceedings of the National Academy of Sciences of the United States of America 114. National Academy of Sciences: E6759-E6766. doi:10.1073/pnas.1701315114.

Ren, H., Y.-C. Chen, X.T. Wang, G.T.F. Wong, A.L. Cohen, T.M. DeCarlo, M.A. Weigand, H.-S. Mii, and D.M. Sigman. 2017. “Nitrogen Cycle: 21st-Century Rise in Anthropogenic Nitrogen Deposition on a Remote Coral Reef”. Science 356. American Association for the Advancement of Science: 749-52. doi:10.1126/science.aal3869.

Wang, X.T., D.M. Sigman, A.L. Cohen, D.J. Sinclair, R.M. Sherrell, K.M. Cobb, D.V. Erler, J. Stolarski, M.V. Kitahara, and H. Ren. 2016. “Influence of Open Ocean Nitrogen Supply on the Skeletal δ15N of Modern Shallow-Water Scleractinian Corals”. Earth and Planetary Science Letters 441. Elsevier B.V.: 125-32. doi:10.1016/j.epsl.2016.02.032.

Costa, K.M., J.F. McManus, R.F. Anderson, H. Ren, D.M. Sigman, G. Winckler, M.Q. Fleisher, F. Marcantonio, and A.C. Ravelo. 2016. “No Iron Fertilization in the Equatorial Pacific Ocean During the Last Ice Age”. Nature 529. Nature Publishing Group: 519-22. doi:10.1038/nature16453.