Everything you need to know about temperature corrections, from a country where they know what cold means
RAC - 9.0 INSTRUMENT ARRIVAL FLIGHT RULES (IFR) ? ARRIVAL PROCEDURES - Transport Canada
See 9.17
Edited to add:
Going back to the OP's question, this section is particularly well written:
AIR - 1.0 GENERAL INFORMATION - Transport Canada
See 1.5.4.
1.5.4b reads
When the current altimeter setting of an airport is set on the subscale of an altimeter, the only time a pilot can be certain that the altimeter indicates the “true” altitude is when the aircraft is on the ground at that airport.
Note that "altimeter setting" is the North American equivalent of QNH.