Forbidden Work of Shabbat with an Altered Form Is Rabbinically Prohibited: Rashi Pesachim 47b "KiLi'Achar"
Altered Work of Shabbat to prevent a non-life-threatening threat: Shabbat 141b-142a
Forbidden Work with an Altered Form on Holidays: Shabbat 117b, 128b, 148a, Pesachim 47b
An Altered Form which Adds to the work being done: Shabbat 148a
Where either participant could have done it alone: Shabbat 92b-93b
Where one of the participants could have done it alone: Shabbat 92b-93b
Where neither of the participants could have done it alone: Shabbat 92b-93b
For Illegal Transport, where one does the lifting and one does the putting-down: Shabbat 93a
In general Forbidden Work, requiring a specific degree of work for each participant for violation: Shabbat 93b