File:Adder (PSF).pngDescriptionAdder (PSF).png English: Line art drawing of an adder. Source Archives of Pearson Scott Foresman, donated to the Wikimedia Foundation Author
File:Adder - European (PSF).pngDescriptionAdder - European (PSF).png English: Line art drawing of the head and tail of a European adder. Source Archives of Pearson Scott Foresman, donated
File:Adder's tongue (PSF).pngDescriptionAdder's tongue (PSF).png English: Line art drawing of the adder's tongue plant. Source Archives of Pearson Scott Foresman, donated to the Wikimedia
File:PSF A-10010.pngDescriptionPSF A-10010.png Raw image from Pearson Scott Foresman donation Date 12 December 2007, 18:46 (UTC) Source scans from source by Pearson Scott
File:PSF A-10012.pngDescriptionPSF A-10012.png Raw image from Pearson Scott Foresman donation Date 12 December 2007, 18:43 (UTC) Source scans from source by Pearson Scott