@article{44ea4a3f2910419c972af01284e33788,
title = "An ultrastructural investigation of early Middle Pennsylvanian megaspores from the Illinois Basin, USA",
keywords = "Pennsylvanian, megaspores, morphology, ultrastructure, ontogeny, PLEUROMEIA-ROSSICA NEUBURG, PHYLOGENETIC IMPLICATIONS, HETEROSPOROUS LYCOPHYTES, ARBORESCENT LYCOPSIDS, WALL ULTRASTRUCTURE, FINE-STRUCTURE, NORTH-AMERICA, MICROSPORES, MORPHOLOGY, HISTORY",
author = "Glasspool, {I. J.} and Collinson, {M. E.} and Scott, {A. C.} and Brain, {A. P. R.} and Plotnick, {R. E.} and F. Kenig",
year = "2009",
month = jul,
doi = "10.1016/j.revpalbo.2008.10.004",
language = "English",
volume = "156",
pages = "62--78",
journal = "Review of Palaeobotany and Palynology",
publisher = "Elsevier",
number = "1-2",
}