Ostry, R. C.

Grand River, Ontario summary pilot watershed report / by: Ostry, R. C.; International Reference Group on Great Lakes Pollution from Land Use Activiti; Hore, R. C.; Grand River Watershed (Ont.) (Language materials, printed)

Saugeen River, Ontario summary pilot watershed report / by: Saugeen River Watershed (Ont.); Ostry, R. C.; International Reference Group on Great Lakes Pollution from Land Use Activities.; Hore, R. C. (Language materials, printed)

The Effect of some waste disposal practices on Great Lakes water quality / by: Ostry, R. C.; International Reference Group on Great Lakes Pollution from Land Use Activities., Task Group C (Canadian Section) (Language materials, printed)