Reference for Eruvin 68:6
א"ל כבר רמי ליה רמי בר חמא לרב חסדא ושני ליה רישא רבי וסיפא רבנן
[represents the view of] Rabbi. [Would then] the first clause [represent the view of] Rabbi and the final clause [that of the] Rabbis? - The other replied: Rami B'Hama has already pointed out this incongruity to R'Hisda who answered him that the first clause was indeed the view of Rabbi while the final one was that of the Rabbis. Rabina said: Both clauses<span class="x" onmousemove="('comment',' Lit., 'all of it'.');"><sup>18</sup></span> represent the view of Rabbi but [the restriction in] the final clause is a preventive measure against the possibility of nipping [the frail reed].<span class="x" onmousemove="('comment',' When removing the 'erub from it. The nipping of a piece of reed is Pentateuchally forbidden and hence prohibited also at twilight. Such possibility need not be provided for in [the case of a tree which is hard and strong.');"><sup>19</sup></span>