A search through the entire database was made possible through providing an English translation of the title or English keywords. One of these fields was mandatory. This constraint may seem irrelevant but for some countries it was a considerable barrier to increased input. One of the goals of SIGLE from the beginning was to facilitate access to grey documents in Europe. Therefore:   SAMPLE ONE  Accession Number 98:4462DE SIGLE  Title  Anaerobic co-treatment of biological waste materials and sewage sludge. Final report. Gemeinsame anaerobe Behandlung von Bioabfall und Klaerschlamm. Abschlussbericht. Author  Risse, H.  Corporate Source  Technische Hochschule Aachen (DE). Lehrstuhl und Inst.fuer Siedlungswasserwirtschaft  Funding Organization  Oswald-Schulze-Stiftung, Gladbeck (DE)  Source  Jan 1998. 83 p. Availability  Available from TIB Hannover: F98B1076+a. Document Type Numerical Data  Country  Germany, Federal Republic of  Language   German  Abstract  The main goals of co-fermentation are sewage sludge stabilisation, production of a cyclable product and minimisation of process emissions. This research project focused on anaerobic wet fermentation. Criteria of evaluation were the quantity and quality of the resulting fermented sludge, biogas, and process water. In view of the scarcity of data on optimum process conditions, the investigations were to provide information, e.g.: Optimum ratio of biological waste to sewage sludge, influence of process conditions (temperature, charge volume, flow rate) on biogas production and process water burden. (orig.)  Classification Code 10U Biomass energy  Terms  BIOLOGICAL WASTES; SEWAGE SLUDGE; ANAEROBIC DIGESTION; METHANE; CHEMICAL OXYGEN DEMAND; AMMONIA; WASTE WATER; PHOSPHORUS; METALS; TEMPERATURE DEPENDENCE; EVALUATION; EXPERIMENTAL DATA. SAMPLE TWO  Accession Number  98:20686GB SIGLE  Title  Switching to cheaper coals for power generation. Author  Carpenter, A.M.  Corporate Source  IEA Coal Research, London (GB). Clean Coal Centre  Number of Report  IEACR-CCC—01  Source  1998. 87 p.