Reference for Berakhot 31:15

והתניא מעין י"ח אמר רב ששת לא קשיא הא ר"ג הא ר' יהושע

But lo, there is a teaching: [Such men are to say] an abstract of the Eighteen Benedictions! Rab Sheshet said : There is no contradiction ; the first being Rabban Gamaliel's view, the latter R. Joshua's.

Jastrow