 | Romberger, J. A. (John Albert), 1925- 4n | (1) |
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 | Romberger, J. A. (John Albert), 1925- 4n; Culture of apical meristems and embryonic shoots of picea abies : approach and techniques / J.A. Romberger, R.J. Varnell, C.A. Tabor. Washington : U.S. Dept. of Agriculture, 1970. | |
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