CHAUDHRI, M. A., KHALID ISLAM, and INAYAT ULLAH. 1995. “?TECHNIQUES FOR INTER-CALIBRATION OF DEAD WEIGHT PRESSURE TESTERS”. Biological Sciences - PJSIR 38 (9-10):375-78. https://v2.pjsir.org/index.php/biological-sciences/article/view/2525.