TY  - JOUR
T1  - On the Organization of the Fossil Plants of the Coal-Measures.--Part IV. Dictyoxylon, Lyginodendron, and Heterangium. 
JF  - Proceedings of the Royal Society of London (1854-1905)
VL  - 21
SP  - 86
EP  - 90
PY  - 1872/01/01/
UR  - http://dx.doi.org/10.1098/rspl.1872.0018
M3  - doi:10.1098/rspl.1872.0018
AU  - Williamson, W.
ER  -