Pillai, N. (1972). Problems on statistics (1st.). Progressive Co. Pvt. Ltd.
Lua i Stíl Chicago (17ú heag.)Pillai, N. Problems on Statistics. 1st. NULL: Progressive Co. Pvt. Ltd, 1972.
Lua MLA (9ú heag.)Pillai, N. Problems on Statistics. 1st. Progressive Co. Pvt. Ltd, 1972.
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