References
- Bell , D. and Bell , J. W. 1980 . A simple approach to the study of attached micro-algae . Journal of Biological Education , 14 ( 1 ) : 3 – 10 .
- Parkinson , D. , Gray , T. R. G. and Williams , S. T. 1971 . Methods for Studying the Ecology of Soil Microorganisms , IBP Handbook No. 19 Oxford : Blackwell .
- Perfil'ev , B. V. and Gabe , D. R. 1969 . Capillary Methods of Investigating Microorganisms , London and New York : Academic Press .