Reference for Taanit 41:5
אמרו לו אי אתיב מר וגריס לא הוה מליך מר אזל תלא נפשיה באסקריא דספינתא אמר אי איכא דשאיל לי במתניתא דר' חייא ורבי אושעיא ולא פשטינא ליה ממתני' נפילנא מאסקריא דספינתא וטבענא
And an old man came forward and cited the following Baraitha: If a man [in his last will and testament] declares, Give a shekel weekly to my sons, but actually they needed a sela'<span class="x" onmousemove="('comment',' Two common shekalim make a sela'.');"><sup>6</sup></span> then they should be given a sela'; but if he declared, Give them a shekel only, then they should be given a shekel. If, however, he declared, On their death others should inherit [their allowance] in their stead, then whether he has declared 'give' or 'give only' they are given a shekel only.<span class="x" onmousemove="('comment',' V. B.B. 129a. Keth. 69a.');"><sup>7</sup></span>