Considering a jointly purchased entity to have parts owned by each individual partner, such that we may consider the entity to have parts donated by each individual: Eruvin 71b
May one merge using money: Eruvin 49a
May one merge using a vessel: Eruvin 49a
May one merge using a meal of minimal value, less than the smallest coin: Eruvin 49a-b
Whether the donation of the meal must be sincere, such that if the donor refuses to give it to one of the residents on request, the partnership is annulled: Eruvin 68a