1. Bernal, M.P., Lopez-Real, J.M. and Scon, K.M. 1993. Bioresource Technol. 43, 35–39.
2. Bhoyar, R.V., Olaniya, M.S. and Bhide, A.D. 1979. Indian I. Environ. Mlth., 21,23–34.
3. Bishop, PL. and Godfrey, C. 1983. BioCycle, 24, 34–39.
4. De Bertoldi, M., Vallini, G., Pera, A. and Zucconi, F. 1982. BioCycle, 23, 45–50.
5. Finstein, M.S., Miller, F.C., MacGregor, S.T. and Psaranos, K.M. 1985. EPA Project Summary (EPA/600/52–851059) U.S. EPA, Washington.