Anaerobic digestion of municipal sludge: theory and practice Aerobic digestion slurry for agricultural applications: theory and practice Exploration of animal ethics theory and practice International trade: theory and practice Urbanization of Chongqing theory and practice On the application of international commercial usages: theory and practice Construction of new science city: theory and practice Exploration of regional financial theory and practice Rhetoric in discourse: theory and practice Systemic functional linguistics: theory and practice