四分律刪繁補闕行事鈔 1.307

1.307

四明結處非法失不之相。初中所明，前已具述，恐有迷忘。謂兩界相接，中無自然，共相錯涉。隔水無橋，或不捨本界而重結之。及界不盡集，羯磨不成，方相不練。並非結法。《五分》云：不唱方相，不成結界。

Fourth, explaining the marks of whether the demarcated place is illegitimate and whether it is lost: What was explained in the first section was already detailed previously, but lest there be confusion and forgetting: That is, where two boundaries adjoin without a natural [boundary] between them, mutually overlapping and entangling. Crossing water without a bridge; or failing to relinquish the original boundary and re-demarcating over it; as well as failing to gather the entire boundary, failing to accomplish the karman, and directional markers being unclear—all these are improper methods of demarcation. The Pañcavargika-vinaya says: 'If directional markers are not proclaimed, demarcating the boundary is not accomplished.'