APA

Hawkes J. G., Hjerting J. P., . (1989). The potatoes of Bolivia : their breeding value and evolutionary relationships. Oxford: Clarendon Press.

Chicago

Hawkes John Gregory, Hjerting J P, . 1989. The potatoes of Bolivia : their breeding value and evolutionary relationships. Oxford: Clarendon Press.

Harvard

Hawkes J. G., Hjerting J. P., . (1989). The potatoes of Bolivia : their breeding value and evolutionary relationships. Oxford: Clarendon Press.

MLA

Hawkes John Gregory, Hjerting J P, . The potatoes of Bolivia : their breeding value and evolutionary relationships. Oxford: Clarendon Press. 1989.