na INLIS000000000025554 Ind 0010-1218007392 Proceedings symposium river recreation management research, January 24-27, 1977, Minneapolis, Minnesota SYMPOSIUM RIVER RECREATION MANAGEMENT AND RESEARCH (1977 : Minnesota) North Central Forest Experimental Station North Central Forest Experimental Station Minnesota North Central Forest Experimental Station 1977 455 p. : ill. ; 29 cm. 455 p. : ill. ; 29 cm. 551.482SYMp 551.482 RIVERS RECREATION MANAGEMENT RESEARCH 1180/79