Reference for Rosh Hashanah 67:15
אלא מאי דרשי בהו והעברת כדרב מתנא דאמר רב מתנא והעברת דרך העברתו תעבירו דקאמר רחמנא נעבריה ביד
[The teru'ahs mentioned in] 'a solemn rest, a memorial of teru'ah,' and in 'thou shalt make proclamation with the shofar of teru'ah' are ordinances of the Torah; the text 'a day of teru'ah it shall b to you' is required for its own lesson.<span class="x" onmousemove="('comment',' I.e., to provide a gezerah shawah; and the third teru'ah is an ordinance of the Soferim.');"><sup>22</sup></span> R'Samuel B'Nahmani said in the name of R'Jonathan: One is ordained by the Torah and two by the Soferim: [That mentioned in] 'and thou shalt make proclamation with the shofar of teru'ah' is ordained by the Torah. [The texts] 'a solemn rest, a memorial of teru'ah' and, 'a day teru'ah it shall be to you', are required for their own lessons.