Yogācārabhūmi-śāstra, Volume 34 (34)

Original text:如是一切外事诸行。前之六种是所摄受事。后之十种是身资具事。以要言之。当知其性皆是无常。何以故。形相转变现可得故。由如是等如前所说。

Explanation: Thus, all these external phenomena and formations—the first six kinds are the matters subsumed and received by the body of the five aggregates, and the latter ten kinds are the matters of the necessities required by the body. In summary, the nature of all these dharmas is impermanent. Why is this said? Because the transformations of the forms and marks of these dharmas can be observed directly in the present, just as was specifically described earlier.