Machar, Ivo, Libuše Hrabí, Monika Millerová, and Olga Vránová. “Didactics of Biology and Ecology in Preparation of Future Teachers of Bilogy and . ”. Envigogika 6, no. 1 (May 5, 2011). Accessed July 23, 2019. https://www.envigogika.cuni.cz/index.php/Envigogika/article/view/335.