APA
Herak M., Stringfield V. T., . (1972). Karst: important karst regions of the northern hemisphere. Amsterdam: Elsevier Publ. Co.
Chicago
Herak Milan, Stringfield V T, . 1972. Karst: important karst regions of the northern hemisphere. Amsterdam: Elsevier Publ. Co.
Harvard
Herak M., Stringfield V. T., . (1972). Karst: important karst regions of the northern hemisphere. Amsterdam: Elsevier Publ. Co.
MLA
Herak Milan, Stringfield V T, . Karst: important karst regions of the northern hemisphere. Amsterdam: Elsevier Publ. Co. 1972.