四分律行事鈔資持記 3.273

3.273

指略中，初顯略。具下，指廣。即《輕重儀》，文有一卷，判決精詳。不覽彼文，何由曉此，故云亦須等也。

Under 'Pointing out the abridgment', first, it reveals the abridgment. The phrase 'In full under...' points to the expansive version: that is the Ritual of Light and Heavy, which is in one fascicle, with rulings that are precise and detailed. Without reading that text, how could one comprehend this? Therefore it says 'one must also...', etc.