The interior planets
[by] V. Axel Firsoff.

APA Citation

Firsoff, V. A. (Valdemar Axel). (1968). The interior planets. Edinburgh: Oliver & Boyd.

MLA Citation

Firsoff, V. A. (Valdemar Axel), 1912-1981. The Interior Planets. Edinburgh: Oliver & Boyd, 1968.

Warning: These citations may not always be complete (especially for serials).