That’s the current official one IN ENGLISH. A USCCB vote was recently taken to begin revision of the English translation. It’s the official translation of the first edition of the Liturgia Horarum (1970) for the U.S., Canada and several other English-speaking countries.
The current TYPICAL edition, however, is the second edition in Latin, promulgated in 1985 This is to be the source for the upcoming English revision. We currently do not expect any final English revision before 2020.
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