Indian standards institution . ISI. (1982). Method for standard penetration test for soils IS: 2131-1981 (1.). Indian standards institution.
Styl cytowania ChicagoIndian standards institution . ISI. Method for Standard Penetration Test for Soils IS: 2131-1981. 1. New Delhi: Indian standards institution, 1982.
Styl cytowania MLAIndian standards institution . ISI. Method for Standard Penetration Test for Soils IS: 2131-1981. 1. Indian standards institution, 1982.