The next step was to secure my victim—my collaborator, I preferred to call him.
It has been stated, too, that Cœlius had more than one collaborator.
"Boomerang" is the joint nom-de-plume of a Young Australian and his collaborator.
Henry softened the rigour of his collaborator's pen in something like half an hour.
Still, we think Wagner might have been mentioned as his collaborator.