Pihera, P., & Svoboda, J. (1997). Heterocyclic [3,2-b]-Fused Pentalenes and Their Benzoannellated Derivatives. Chemické Listy, 91(8). Získáno z http://w-ww.chemicke-listy.cz/ojs3/index.php/chemicke-listy/article/view/2751