Reference for Rosh Hashanah 16:6

ולשמיטין: מנלן דכתיב (ויקרא כה, ד) ובשנה השביעית שבת שבתון יהיה לארץ וגמר שנה שנה מתשרי דכתיב (דברים יא, יב) מראשית השנה

in from the beginning of the year.<span class="x" onmousemove="('comment',' Deut. XI, 12, which refers to Tishri.');">⁹</span> But let us learn that it is Nisan from analogy with the word 'year' in the text, it is the first to you of the months of the year?<span class="x" onmousemove="('comment',' Ex. XII, 2.');">¹⁰</span> - We draw an analogy to a year with which months are not mentioned from a year with which months are not mentioned, but we do not draw an analogy to a year with which months are not mentioned from a year with which months are mentioned.<span class="x" onmousemove="('comment',' V. supra p, 7a.');">¹¹</span>

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