Husa, Michal; Kratochvil, Bohumil; Sedmera, Petr; Havlicek, Vladimir; Votavova, Hana; Cvak, Ladislav; Bulej, Petr; Jegorov, Alexandr Collection of Czechoslovak Chemical Communications, 1998 , vol. 63, # 3 p. 425 - 433