1. ASTM Designation D 388-98a—Standard Classification of Coals by Rank.
2. Nature of the porosity in American coals;Gan;Fuel,1972
3. Influence of gas production induced volumetric strain on permeability of coal;Harpalani;Geotech. Geol. Eng.,1997
4. The internal structure of coal;King,1944
5. Coalbed methane characteristics of Gates Formation coals, Northeastern British Columbia: effect of maceral composition;Lamberson;AAPG Bull.,1993