EP1362924-A  O'KEEFE D M ET AL: "Influence of methane enrichment by aeration of recirculated supernatant on microbial activities during anaerobic digestion" BIORESOURC TECHNOL;BIORESOURCE TECHNOLOGY 2000 ELSEVIER SCIENCE LTD, EXETER, ENGL, Bd. 71, Nr. 3, 2000, Seiten 217-224, XP002258267;  STEPHENSON R J ET AL: "Effects of oxygenation and upflow liquid velocity on a coupled anaerobic/aerobic reactor system" WATER RESEARCH, ELSEVIER SCIENCE PUBLISHERS, AMSTERDAM, NL, Bd. 33, Nr. 12, August 1999 (1999-08), Seiten 2855-2863, XP004174053 ISSN: 0043-1354;  ZHANG R H ET AL: "Anaerobic treatment of swine waste by the anaerobic sequencing batch reactor" TRANS ASAE;TRANSACTIONS OF THE ASAE MAY-JUN 1997 ASAE, ST. JOSEPH, MI, USA, Bd. 40, Nr. 3, Mai 1997 (1997-05), Seiten 761-767, XP009019011EP1362924-A2  STEPHENSON R J ET AL: &quot;Effects of oxygenation and upflow liquid velocity on a coupled anaerobic/aerobic reactor system&quot; WATER RESEARCH, ELSEVIER SCIENCE PUBLISHERS, AMSTERDAM, NL, Bd. 33, Nr. 12, August 1999 (1999-08), Seiten 2855-2863, XP004174053 ISSN: 0043-1354;  STEPHENSON R J ET AL: &quot;Effects of oxygenation and upflow liquid velocity on a coupled anaerobicaerobic reactor system&quot; WATER RESEARCH, ELSEVIER SCIENCE PUBLISHERS, AMSTERDAM, NL, Bd. 33, Nr. 12, August 1999 (1999-08), Seiten 2855-2863, XP004174053 ISSN: 0043-1354;  O&apos;KEEFE D M ET AL: &quot;Influence of methane enrichment by aeration of recirculated supernatant on microbial activities during anaerobic digestion&quot; BIORESOURC TECHNOL;BIORESOURCE TECHNOLOGY 2000 ELSEVIER SCIENCE LTD, EXETER, ENGL, Bd. 71, Nr. 3, 2000, Seiten 217-224, XP002258267;  ZHANG R H ET AL: &quot;Anaerobic treatment of swine waste by the anaerobic sequencing batch reactor&quot; TRANS ASAE;TRANSACTIONS OF THE ASAE MAY-JUN 1997 ASAE, ST. JOSEPH, MI, USA, Bd. 40, Nr. 3, Mai 1997 (1997-05), Seiten 761-767, XP009019011EP1362924-B1  O'KEEFE D M ET AL: "Influence of methane enrichment by aeration of recirculated supernatant on microbial activities during anaerobic digestion" BIORESOURC TECHNOL;BIORESOURCE TECHNOLOGY 2000 ELSEVIER SCIENCE LTD, EXETER, ENGL, Bd. 71, Nr. 3, 2000, Seiten 217-224, XP002258267;  STEPHENSON R J ET AL: "Effects of oxygenation and upflow liquid velocity on a coupled anaerobic/aerobic reactor system" WATER RESEARCH, ELSEVIER SCIENCE PUBLISHERS, AMSTERDAM, NL, Bd. 33, Nr. 12, August 1999 (1999-08), Seiten 2855-2863, XP004174053 ISSN: 0043-1354;  ZHANG R H ET AL: "Anaerobic treatment of swine waste by the anaerobic sequencing batch reactor" TRANS ASAE;TRANSACTIONS OF THE ASAE MAY-JUN 1997 ASAE, ST. JOSEPH, MI, USA, Bd. 40, Nr. 3, Mai 1997 (1997-05), Seiten 761-767, XP009019011