Below are some sources of information about plankton for if you want to know more. There are quite a few books about plankton, but there is also plenty on the internet, including beautiful photos and videos!
These books are interesting if you want to know more about plankton. Unfortunately there is no Dutch book with extensive information about zooplankton (hence this website!).
Coastal Plankton: Photo Guide for European Seas. Otto Larink & Wilfried Westheide. Verlag Dr. Friedrich Pfeil, München. This is THE book to buy if you want to know more about coastal plankton. It is full of beautiful pictures and explanations about many different plankton groups.
Ocean Drifters. Richard Kirby. Studio Cactus Ltd. A photo book with beautiful images of plankton.
Marine Plankton, a practical guide. G.E. Newell & R. C. Newell. Hutchingson Educational, London. A very handy overview of the different shelf groups with practical explanations. Only digitally available.
Marine zooplankton of southern Britain. Dave Conway. Marine Biological Association, Plymouth. A very detailed work in three parts that can be used to identify many European marine zooplankton taxa, also with a lot of background information. Free download.
Marine Plankton: A practical guide to ecology, methodology, and taxonomy. Claidia Castellani & Martin Edwards. Oxford University Press, Oxford. A pricey but very comprehensive book with which many plankton species can be identified. Also a lot of background information, including distribution data based on the Continuous Plankton Recorder.
Das Leben im Wassertropfen. Heinz Streble & Dieter Krauter. Kosmos, Stuttgart. A very comprehensive German book on freshwater microfauna and flora.