中国科学院数学与系统科学研究院期刊网
A REMARK ABOUT UNIQUENESS FOR THE PARTIAL DIFFERENTIAL EQUATIONS OF NON-PRINCIPAL TYPE
王光寅;麦明澂;陆柱家
Acta Mathematica Sinica, Chinese Series . 1979, (6): 713 -718 .  DOI: 10.12386/A1979sxxb0065