Mouse in science fiction

[Leonard Wibberly fans need not apply]

I was reading Grant Callin's _Saturnalia_ (1986) last week, and was taken
aback when the viewpoint character used a mouse to mark his target
position
in the navigational computer.

Obviously, it wouldn't take great clairvoyance to predict the existence
of a computer mouse in 1986. Heck, even I'd used one by then. However,
its use in a serious manner (space****p piloting) seems to be fairly
foresighted. Does anybody have an earlier sighting of a mouse being
used in a work-a-day manner in an SF setting?

BTW, I quite enjoyed both this, and its sequel, _A Lion on Tharthee_.

-- 
Michael F. Stemper
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