Zagwijn, W. H. (1960). Aspects of the Pliocene and early Pleistocene vegetation in the Netherlands. Utig.-Mij. "Ernest van Aelst".
Chicago-viite (17. p.)Zagwijn, Waldo Heliodoor. Aspects of the Pliocene and Early Pleistocene Vegetation in the Netherlands. Maastricht: Utig.-Mij. "Ernest van Aelst", 1960.
MLA-viite (8. p.)Zagwijn, Waldo Heliodoor. Aspects of the Pliocene and Early Pleistocene Vegetation in the Netherlands. Utig.-Mij. "Ernest van Aelst", 1960.
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