Antedating of "double click" (verb and noun)

[Hugo]

double-click, v. (OED: 1984)
double click, n. (OED: 1985)

Raster Graphics for Interactive Programming Environments (CSL-79-6) by
Robert F. Sproull, June 1979.

First a verb:

[Begin]
Graphical input. The user is provided with a "mouse," a coordinate input
device with three pushbuttons. The mouse rolls along a table top and is
tracked by a cursor that moves on the screen. The mouse can thus be used to
point to objects already displayed on the screen, or simply to identify a
coordinate position. The three keys are remarkably versatile, provided the
software for handling them is sufficient: for example, combinations of keys
can be struck as "chords"; a single key action can be distinguished from
two key depressions in rapid succession ("double clicking").
[End]

And a noun three times:

[Begin]
Some input techniques require careful timing that is not provided by the
event mechanism alone. For example, consider distinguishing a "single
click" (key goes down, then up) from a "double click" (key goes down, up,
down again within 1/3 second, then up). After observing the first two
transition events (down,up), the application program needs to wait for
either a down transition or 1/3 second, whichever comes first. Because
Dlisp Rins in a time-sharing environment, it cannot perform such accurate
timing. Adis provides an internal timer that is started whenever one of a
set of "starting transitions" occurs and is stopped whenever one in a set
of "stopping transitions" occurs. If the timer expires before a "stopping
transition" occurs, a timeout event is generated. Thus the program trying
to distinguish single and double clicks will receive one of two input
sequences: down, up, timeout (single click); down, up, down, up, timeout
(double click).
[End]

Possible OCR errors not corrected in quoted text; a PDF scan is also
available.
https://archive.org/details/bitsavers_xeroxparctterGraphicsforInteractiveProgrammingEnvi_2695970

And there may be a slightly earlier example from the same paper, as the
inside front cover suggests: "A shortened version of this paper appeared in
Computer Graphics, Summer 1979."

"Single click" is not in the OED and is also used here.

Hugo

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