פירוש על בבא מציעא 11:2

As R’ Chiya taught in a Baraisa. See Rashi ד'ה שניהם who raises a question: Why is the Gemara quoting a Baraisa of R’ Chiya, when this ruling is clearly mentioned in a Mishna (Shavuos 44b)? Rashi asked: Why didn’t [the Gemara] cite the Mishna of Shavuos (44b), instead of R’ Chiya’s Baraisa? A Mishna is usually recognized as more authoritative than a Baraisa. We can answer: That Rebbe Yehudah the Prince, author of the Mishna, taught this Mishna as a result of his conversation with R’ Chiya, as is evident there (Shavuos 47b).
The Gemara in Shavuos 47b: We learned in a Baraisa: Rebbe said: The trouble of this oath is for what purpose? R’ Chiya said to [Rebbe]: We learned in a Baraisa: Both swear and collect from the householder. It seems that Rebbe had his doubts about this oath and was convinced by R’ Chiya to incorporate this ruling into the Mishna.