APA (7e ed.) Bronvermelding

Roos, G. (1935). Comparative researches on the variation of the constituents of coal of one seam from south Limburg: The Netherlands. Van Aelst Bros.

Chicago (17e ed.) Bronvermelding

Roos, Gerrit. Comparative Researches on the Variation of the Constituents of Coal of One Seam from South Limburg: The Netherlands. Maastricht: Van Aelst Bros, 1935.

MLA (8e ed.) Bronvermelding

Roos, Gerrit. Comparative Researches on the Variation of the Constituents of Coal of One Seam from South Limburg: The Netherlands. Van Aelst Bros, 1935.