Support growing potatoes at 4000m altitude in Peru (1993)

Aardappelteelt-op-4000-m-hoogte-Peru.-Links-de-hybride-aardappel-en-in-het-midden-de-inlandse-aardappel-juli-1993
Project-inlandse-aardappel-Hoogland-Indianen-Peru-juni-1993