author
A little-known Finnish coauthor linked to an early travel account about Argentina and Uruguay, Ossi Donner survives in the record mainly through the book itself rather than a well-documented public life.

by Arno Donner, Ossi Donner
Ossi Donner is credited alongside Arno Donner as a coauthor of Matkustus Argentinassa ja Uruguayssa (“Travels in Argentina and Uruguay”), a Finnish travel book available through Project Gutenberg. Reliable biographical information about Ossi Donner appears to be very sparse in the sources I could confirm.
Because the published record is so limited, it is safest to describe Ossi Donner as a historical Finnish author or collaborator known from this travel work, rather than to repeat uncertain personal details. For readers, that means the book is best approached through its subject matter and period perspective instead of through a detailed author biography.