1. Sediments of the modern Niger delta. A summary and review;Allen,1970
2. 17αH-hopane identified in oil shale of the Green River Formation (Eocene) by C13 nmr;Balogh;Nature (London),1973
3. Analysis of lipid fractions from environmental and geological sources by computerized gas chromatography—mass spectrometry;Brooks,1977
4. Organic geochemistry of some sediments and petroleum of the Niger delta: “The terpenoid aspect”;Ekweozor,1978
5. Pentacyclic triterpanes of the hopane type as ubiquitous geochemical markers: origin and significance;Ensminger,1974