Block, T. A., Rhoads, A. F., & Aniśko, A. (2011). Aquatic plants of Pennsylvania: A complete reference guide. University of Pennsylvania Press.
Chicago-viite (17. p.)Block, Timothy A., Ann Fowler Rhoads, ja Anna Aniśko. Aquatic Plants of Pennsylvania: A Complete Reference Guide. Philadelphia: University of Pennsylvania Press, 2011.
MLA-viite (9. p.)Block, Timothy A., et al. Aquatic Plants of Pennsylvania: A Complete Reference Guide. University of Pennsylvania Press, 2011.
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