"Frank D. Masch & Associates." . . "MASCH F.D." . . "Simulation of water quality in streams and canals : theory and description of the QUAL-I mathematical modeling system"@en . . "Simulation of water quality in streams and canal theory and description of the QUAL-1 mathematical modeling system"@en . "Simulation of water quality in streams and canals theory and description of the QUAL-I mathematical modeling system" . . . . . . "Simulation of water quality in streams and canals; theory and description of the QUAL-I mathematical modeling system"@en . . . . . . . . . "Simulation of water quality in streams and canals: theory and description of the qual- i mathematical modeling system" . . . . . . .