(1893). West Virgnia Agricultural Experiment Station: научное издание. Special Bulletin No 30 : Address and notes on sheep. (By A. D. Hopkins).
Chicago-viite (17. p.)West Virgnia Agricultural Experiment Station: научное издание. Special Bulletin No 30 : Address and Notes on Sheep. (By A. D. Hopkins). 1893.
MLA-viite (9. p.)West Virgnia Agricultural Experiment Station: научное издание. Special Bulletin No 30 : Address and Notes on Sheep. (By A. D. Hopkins). 1893.
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