Biblio

“Methane digestors for fuel gas and fertilizer : with complete instructions for two working models”. L. John Fry, Santa Barbara, CA, USA, p. 45 p., 1973.

I. N. Structural Ghaziabad, “Ferrocement applications”. Structural Engineering Research Centre, Ghaziabad, India, p. 25 p.: fig., photogr.

Uof Aberdee Science, “The potential of small-scale biogas digesters to alleviate poverty and improve long term sustainability of ecosystem services in Sub-Saharan Africa..”. Department for International Development, DFID, S.l., p. 57 p.; fig.