Conservation of nature /
Astanin, L. P.
Erickson, John,1929-2002,former owner.StEdNL
Erickson, Ljubica,former owner.StEdNL
Blagosklonov, K. N.(Konstantin Nikolaevich),1910-
Moscow : Progress Publishers,
1983.
English version of the revised Russian text.
Translation of Okhrana prirody.
John and Ljubica Erickson collection.
Nature conservation.