Notes: Not seen. Citation from Radchenko (pers. comm.). Signed for printing ("podpisano k pechati") 12 July 1989, but actually published in 1990.
Notes: Age of Bitterfeld amber remains equivocal between late Eocene and Oligocene
Notes: January-February issue. Date signed for printing ("podpisano k pechati"): 30 January 1990.