8Hcnnnigar G W. Advances in gas leak detection[J]. Pipe and Gas Journal, 1985,212(11) :39-42.
9De Read J R. Comparision between ultrasonic and magnetic flux pigs for fipelines inspection [J]. Pipes and Pipelines Int.1987(1) :7-15.
10Chet Sandberg. The Application of a continuous leak detection system to pipelines and associated equipment[J]. IEEE Transaction on Industry Applications, 1989,25(5) :906-909.
