Reference for Shabbat 39:3
אין נותנין את הפת כו': איבעיא להו תחתון האיך דגבי תנור או דילמא תחתון האיך דגבי האור ת"ש ר"א אומר כדי שיקרמו פניה המדובקין בתנור:
It was taught: Hanina said: Whatever is as the food of the son of Derusai may be kept on the stove,<span class="x" onmousemove="('comment',' On the Sabbath; i.e., if it was a third done before. ');"><sup>7</sup></span> though it is not swept [clear of the cinders] and besprinkled with ashes.<span class="x" onmousemove="('comment',' V. infra 36b. ');"><sup>8</sup></span> BREAD MAY NOT BE PUT, etc. The scholars propounded: Does the BOTTOM [surface] mean the one by the oven, or perhaps BOTTOM means the one by the fire?<span class="x" onmousemove="('comment',' The oven or stove would appear to have been without a closed bottom, but perhaps consisted of a number of bars over the fire, and the loaves were placed thereon and pressed to the sides of the oven; v. T.A., pp. 87f- The question is whether BOTTOM surface means the surface directly on the open bars facing the fire underneath, or that adhering to the side of the oven. ');"><sup>9</sup></span>