Indian standards institution . ISI. (1975). Test code for disc harrows,IS: 7640-1975. ISI.
استشهاد بنمط شيكاغوIndian standards institution . ISI. Test Code for Disc Harrows,IS: 7640-1975. : ISI, 1975.
MLA استشهادIndian standards institution . ISI. Test Code for Disc Harrows,IS: 7640-1975. ISI, 1975.