1. Treatment of liquid;BOC,1976
2. Improvements in or relating to scraping and scumming apparatus for sedimentation tanks;Bolton,1957
3. Evaluation of three types of fish rearing ponds;Burrows;US Department of the Interior Fish and Wildlife Service, Research Report 39,1955
4. The rectangular circulating rearing pond;Burrows,1970
5. Trout culture in vertical units;Buss,1970