TY - RPRT TI - Transcontinental geophysical survey (35° - 39° N) geologic map from the East Coast of the United States to 87° W longitude AU - Ronald Willden AU - J. C. Reed AU - J. E. Carlson PY - 1968 DO - 10.3133/i535c UR - https://pubs.usgs.gov/publication/i535C ID - i535C ER -