Gaya APA

van, C, P. (1977). An Early Paleozoic Continental Rift System In Galicia (Nw Spain) . : D. Reidel Publishing Company.

Gaya MLA

van, Calsteren, P.W.C.. "An Early Paleozoic Continental Rift System In Galicia (Nw Spain)". : D. Reidel Publishing Company, 1977. Text.