Jamali, Abdul Rauf, Khan, Waseem, Chandio, Ali Dad, Anwer, Zubai, AND Jokhio, Muhammad Hayat. " Effect of Cryogenic Treatment on Mechanical Properties of AISI 4340 and AISI 4140 Steel" Mehran University Research Journal of Engineering and Technology [Online], Volume 38 Number 3 (1 July 2019)