Viljoen, J. H. A. (1992). Lithostratigraphy of the Collingham Formation (Ecca Group), including the Zoute Kloof, Buffels River and Wilgehout River Members and the Matjiesfontein Chert Bed. Geological Survey.
Chicago Style (17th ed.) CitationViljoen, J. H. A. Lithostratigraphy of the Collingham Formation (Ecca Group), Including the Zoute Kloof, Buffels River and Wilgehout River Members and the Matjiesfontein Chert Bed. Pretoria: Geological Survey, 1992.
MLA (9th ed.) CitationViljoen, J. H. A. Lithostratigraphy of the Collingham Formation (Ecca Group), Including the Zoute Kloof, Buffels River and Wilgehout River Members and the Matjiesfontein Chert Bed. Geological Survey, 1992.
Warning: These citations may not always be 100% accurate.