1. The American species of Asterophyllites, Annularia, and Sphenophyllum;Abbott;Bull. Am. Palaeont.,1958
2. A revision of the seed impressions of the British coal measures;Arber;Ann. Bot.,1914
3. The heterogeneity of the form genus Mariopteris Zeiller. A comparative morphological study with special reference to the frond of West-European species;Boersma;Drukkerij Elinkwijk-Utrecht,1972
4. A species of compressed lycopod sporophyll from the Upper Coal Measures of Somerset;Boulter;Palaeontology,1968
5. BOUREAU, E. Traité de Paléobotanique. Tome ii, 1967. Bryophyta, Psilophyta, Lycophyta. Tome iii, 1964. Sphenophyta, Noeggerathiophyta. (Tome ii—Groups B, D, F & G Lycopods) (Tome iii—Groups A, C & F Calamites and Sphenophylls)