Reference for Sanhedrin 104:26
ואימא שריפה מדאמר רחמנא בת כהן בשריפה מכלל דהא לאו בת שריפה היא
<b><i>MISHNAH</i></b>. <font>STRANGULATION WAS THUS PERFORMED</font>: — THE CONDEMNED MAN WAS <font>LOWERED INTO DUNG UP TO HIS ARMPITS</font>, THEN A HARD CLOTH WAS PLACED WITHIN A SOFT ONE, WOUND ROUND HIS NECK, AND THE <font>TWO ENDS PULLED IN OPPOSITE DIRECTIONS UNTIL HE WAS DEAD.</font> <b><i>GEMARA</i></b>. Our Rabbis taught: [<i>And the man that committeth adultery with another man's wife, even he that committeth adultery with his neighbour's wife the adulterer and the adulteress shall surely be put to death</i>].<span class="x" onmousemove="('comment',' Ibid. XX, 10. ');"><sup>23</sup></span> '<i>The man</i>' excludes a minor; '<i>that committeth adultery with another</i> man's <i>wife</i>' <font>excludes the wife of a minor</font>; '<i>even he that <font>committeth adultery with his</font></i><font> neighbour's <i>wife</i>' excludes the wife of a heathen</font>; 'shall surely be put to death', by strangulation. You say, by strangulation; but perhaps one of the other deaths decreed by the Torah is meant here? — I will answer you: Whenever the Torah decrees an unspecified death penalty, you may not interpret it stringently but leniently:<span class="x" onmousemove="('comment',' Lit., 'attract it to stringency etc'. Hence strangulation, the easiest of deaths, must be meant. ');"><sup>24</sup></span> this is R. Josiah's view. R. Jonathan said: Not because strangulation is the most lenient death, but because by <font>every unspecified death in the Torah strangulation is meant.</font> Rabbi [proceeding to demonstrate this] said: Death by God is mentioned in Scripture;<span class="x" onmousemove="('comment',' E.g., God's slaying of Onan, Gen. XXXVIII, 10. ');"><sup>25</sup></span> and death by man is also decreed. Just as the death by God<span class="x" onmousemove="('comment',' I.e., a normal death, which leaves the body intact. ');"><sup>26</sup></span> leaves no mark [of violence on the body], so also death by man must leave no mark [of violence], a condition which only strangling fulfils. But may it not apply to burning?<span class="x" onmousemove="('comment',' Since, as explained above, an inner fire was applied, leaving the body intact. ');"><sup>27</sup></span> Since the Divine Law explicitly decreed burning for a priest's adulterous daughter, it follows that the adulterous married [Israelite] woman is not put to death by burning.