Dyfyniad APA

United States Department of Agriculture, & Natural Resources Conservation Service. (1995). Soil survey laboratory information manual. Lincoln: National Soil Survey Center.

Dyfyniad Arddull Chicago

United States Department of Agriculture, và Natural Resources Conservation Service. Soil Survey Laboratory Information Manual. Lincoln: National Soil Survey Center, 1995.

Dyfyniad MLA

United States Department of Agriculture, và Natural Resources Conservation Service. Soil Survey Laboratory Information Manual. Lincoln: National Soil Survey Center, 1995.

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.