Analysis of information sources in references of the Wikipedia article "7×57mm Mauser" in English language version.
La presión desarrollada en la recámara por la expansión de los gases de combustión de la pólvora sin humo equivale á 3.500 kilogramos – The pressure developed in the chamber by expansion of the combustion gases of smokeless gunpowder equals 3,500 kg/cm2 (49782 psi)