1. Natural and artificial diagenesis of coal macerals;Allan,1975
2. Variation in the content and distribution of high molecular weight hydrocarbons in a series of coal macerals of different ranks;Allan,1977
3. Reflectance et fluorescence des organoclastes du Toarcien du bassin de Paris en fonction de la profoundeur et de la temperature;Alpern;Rev. Inst. Fr. Petrole,1978
4. Botryococcus and the algal coals. Part II. The boghead controversy and the morphology of the boghead algae;Blackburn;Trans. Roy. Soc. Edin.,1936