varietatea plantelor

The choise of lucerne varieties in the Netherland de: Scheijgrond, W.; Vos, H.; Zikken, H. (Text tipărit)

Research on varieties in connection with rhe Netherlands list of varieties de: Groenewolt, J.K. (Text tipărit)

Research on varieties on behalf of the registration de: Nijdam, F.E. (Text tipărit)