TAD B3.7 R.9 :תחומוה כתיבן בספרא‏ : its boundaries are written in the document
See the entire entry for b_ prep. in, with

TAD B3.7 R.9 :תחומוה כתיבן בספרא [ז]נ[ה] מן תחת ומ[ן ע]ל‏ : its borders are written in this document below and above
See the entire entry for mn@tḥwt adv. from below, below