I did a cursory google search of
poker "hand range" with a specified custom date range and this is the earliest citation I found. FYI, the quotes in the search term indicate a literal phrase that must be present to be considered a match. It's in French and dated 11/30/1999:
Original French:
Dans cette situation, une seule main, QJ, à une chance sur deux de s’imposer contre une seule des mains de la hand range d’un tight raiser, TT. De ce fait, un bon joueur doit avoir la discipline de ne pas rentrer sans avoir au moins {JJ, AKs, AKo}
Translated to English by Google:
In this situation, only one hand, QJ, has a 50/50 chance of winning against just one hand in a tight raiser's hand range, TT. Therefore, a good player must have the discipline not to return without having at least {JJ, AKs, AKo}
Source:
https://www.ruedesjoueurs.com/poker/...s-preflop.html
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The next earliest citation I found searching for
poker "range of hands" is this cardplayer article from 12/31/1991:
If he reraises, then at least I can put him on a range of hands such as a draw, two pair, set, etc.
Source:
https://www.cardplayer.com/poker-new...tilt-1k-monday