@misc{Hunter_George_W._(1873–1948)_Problems_[cop., author={Hunter, George W. (1873–1948)}, copyright={Public Domain}, address={New York}, howpublished={online}, year={[cop. 1940]}, publisher={American Book Company}, language={eng}, title={Problems in biology}, type={Text}, URL={http://www.rcin.org.pl/Content/138590/PDF/WA488_173604_2019728_Problems-in-biology.pdf}, keywords={Biology, Biology - living creatures and their surroundings - plant food - human relations to other living creatures}, }