TY  - BOOK
ED  - National Education Association
ED  - U.S. Department of the Interior. National Park Service
TI  - A Guide to Planning and Conducting Environmental Study Area Workshops
U1  - 363.70071 23
PY  - 1972///
CY  - Washington, D.C.
PB  - National Park Service
N1  - Referencias bibliográficas: pp. 49-50
ER  -