TY - RPRT TI - APRAS; analytic petroleum resource appraisal system; microcomputer programs for play analysis using a field-size model AU - R. A. Crovelli AU - R.H. Balay PY - 1992 DO - 10.3133/ofr9221a UR - https://pubs.usgs.gov/publication/ofr9221A ID - ofr9221A ER -