00563nam a2200157 4500 10018 10018 Weitzel, R L Methods and Measurements of Periphyton Communities: a review USA: ASTM, 1979. Freshwater algae--Measurement Freshwater microbiology--Methodology Algal communities Water quality biological assessment--Methodology ASTM http://books.google.com.pk/books/about/Methods_and_Measurements_of_Periphyton_C.html?id=eEVRAAAAMAAJ&redir_esc=y BK 0 0 0 0 REF REF REF 2014-09-17 0 620.8AST (Shelf - 41E) 16649 2014-09-17 00:00:00 BK