GENEVA, June 20 -- PETROCHINA COMPANY LIMITED (9 Dongzhimen North StreetDongcheng District, Beijing 100007), 中国石油天然气股份有限公司 (中国北京市东城区东直门北大街9号), CNPC R & D (DIFC) COMPANY LIMITED (Unit OT 17-41/42, Central Park Towers, Dubai International Financial Centre415747), 中国石油迪拜研究院 (阿拉伯联合酋长国迪拜国际金融中心中央花园办公楼17-41/42), BEIJING PETROLEUM MACHI...