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Hulings, N. C. (1971) Proceedings of the First International Conference on Meiofauna. Smithsonian Contributions To Zoology, 76:1-220. (available online)
Hulings, N. C. and Gray, J. S. (1971) A Manual For The Study Of Meiofauna. Smithsonian Contributions To Zoology, 78:1-104. (available online)
Higgins, R. P. and Thiel, H. (Eds.) (1988) Introduction to the Study of Meiofauna. Smithsonian Institution Press, Washington D.C., U.S.A., pp.488.
Giere, O. (2009) Meiobenthology. The Microscopic Motile Fauna of Aquatic Sediments. Springer-Verlag, Berlin, Germany, pp.527.
Schmidt-Rhaesa, A. (2020) Guide to the Identification of Marine Meiofauna. Verlag Dr. Friedrich Pfeil, München, Germany, pp.607.
Keys (or key taxonomic publications)
Bartsch, I. (2006) Halacaroidea (Acari): a guide to marine genera. Organisms, Diversity and Evolution, 6:1-104.
Fontoura, P.; Bartels, P. J.; Jørgensen, A.; Kristensen, R. M. and Hansen, J. G. (2017) A dichotomous key to the genera of the Marine Heterotardigrades (Tardigrada). Zootaxa, 4294:1-45. doi:10.11646/zootaxa.4294.1.1
Huys, R.; Gee, J. M.; Moore, C. G. and Hamond, R. (1996) Marine and Brackish Water Harpacticoid Copepods, Part I. Barnes, R. S. K. and Crothers, J. H. (Eds.) Synopses of the British Fauna (New Series), No. 51. Field Studies Council, United Kingdom, pp.352.
Platt, H. M. and Warwick, R. M. (1983) Freeliving Marine Nematode. Part I. British Enoplids. Kermack, D. M. and Barnes, R. S. K. (Eds.) Synopses of the British Fauna (New Series), No. 28. Cambridge University Press, United Kingdom, pp.307.
Platt, H. M. and Warwick, R. M. (1988) Free Living Marine Nematodes. Part II. British Chromadorids. Kermack, D. M. and Barnes, R. S. K. (Eds.) Synopses of the British Fauna (New Series), No. 38. E.J. Brill/Dr. W. Backhuys, pp.502.
Todaro, M. A.; Sibaja-Cordero, J. A.; Segura-Bermúdez, O. A.; Coto-Delgado, G.; Goebel-Otárola, N.; Barquero, J. D.; Cullell-Delgado, M. and Dal Zotto, M. (2019) An Introduction to the Study of Gastrotricha, with a Taxonomic Key to Families and Genera of the Group. Diversity, 11:1-25. doi:10.3390/d11070117
Warwick, R. M.; Platt, H. M. and Somerfield, P. J. (1998) Free-living Marine Nematode. Part III. Monhysterids. Barnes, R. S. K. and Crothers, J. H. (Eds.) Synopses of the British Fauna (New Series), No. 53. Field Studies Council, United Kingdom, pp.296.
Wieser, W. (1953) Free-Living Marine Nematodes. I. Enoploidea. Reports of the Lund University Chile Expedition 1948-49, No. 10. C.W.K. Gleerup, Lund, Sweden, pp.155.
Wieser, W. (1954) Free-Living Marine Nematodes. II. Chromadoroidea. Reports of the Lund University Chile Expedition 1948-49, No. 17. C.W.K. Gleerup, Lund, Sweden, pp.148.
Wieser, W. (1956) Free-Living Marine Nematodes. III. Axonolaimoidea and Monhysteroidea. Reports of the Lund University Chile Expedition 1948-49, No. 26. C.W.K. Gleerup, Lund, Sweden, pp.115.
Wieser, W. (1959) Free-Living Marine Nematodes. IV. General Part. Reports of the Lund University Chile Expedition 1948-49, No. 34. C.W.K. Gleerup, Lund, Sweden, pp.111.
MeioChile (all things meio in Chile)
NeMys (the definitive nematode species list)