00394nam a2200109Ia 4500008004100000082002400041100001600065245008300081260002900164490007100193650002000264220204s9999    xx            000 0 und d  a631.11:001.814bSHA  aSHANER, W W 0aFarming systems research and development: Guidelines for developing countries.  aColoradobWestviewc1982  aWestview special studies in agriculture/aquaculture science policy  aFarming systems