Tertiary coals in south Texas : anomalous cannel-like coals of Webb County (Claiborne Group, Eocene) and lignites of Atascosa County (Jackson Group, Eocene)--geologic setting, character, source-rock and coal-bed methane potential : field trip guidebook
"The 1999 AAPG Annual Convention, Energy Minerals Division, Field Trip 15, April 14-15, 1999."
Includes bibliographical references.
Also available via Internet from the USGS web site (PDF file only). Address as of 5-11-00: http://pubs.usgs.gov/pdf/of/ofr99301/ofr99301.pdf ; current access is available via PURL.