Reference for Sheviit 3:6
גָּדֵר שֶׁיֶּשׁ בּוֹ עֶשֶׂר אֲבָנִים שֶׁל מַשְּׂאוֹי שְׁנַיִם שְׁנַיִם, הֲרֵי אֵלּוּ יִנָּטֵלוּ. שִׁעוּר גָּדֵר, עֲשָׂרָה טְפָחִים. פָּחוֹת מִיכַּן, מְחַצֵּב וְגוֹמְמוֹ עַד פָּחוֹת מֵהָאָרֶץ טֶפַח. בַּמֶּה דְבָרִים אֲמוּרִים, מִתּוֹךְ שֶׁלּוֹ, אֲבָל מִתּוֹךְ שֶׁל חֲבֵרוֹ, מַה שֶּׁהוּא רוֹצֶה, יִטֹּל. בַּמֶּה דְבָרִים אֲמוּרִים, בִּזְמַן שֶׁלֹא הִתְחִיל בּוֹ מֵעֶרֶב שְׁבִיעִית. אֲבָל אִם הִתְחִיל בּוֹ מֵעֶרֶב שְׁבִיעִית, מַה שֶּׁהוּא רוֹצֶה, נוֹטֵל:
A wall that has ten stones, each [stone] a two-person load, may be removed. The height of a wall is ten handbreadths. Less than this, and he should chisel and raze until it is less than one handbreadth from the ground. When is the aforementioned true? When dealing with one's own [field]. However, within that of one's neighbor, what one wants one may take. When is the aforementioned true? When one didn't start [removing the stones] prior to the seventh year. But if one started prior to the Sabbatical year, what one wants one may take [even on one's own field into the Sabbatical year].