Person Y giving money to Person X to establish the meal for him: Eruvin 81a-b
Adding to the meal without letting the participants know one has done so, if some or all of the food is removed: Eruvin 80b
Adding to the meal without letting the participants know one has done so, if new residents arrive, requiring more food to be added: Eruvin 80b, 81b
May a person put out the meal on behalf of another person, without actually transferring ownership of the meal to him: Eruvin 80a
May the wife in a household contribute to the merging meal without her husband's knowledge: Eruvin 80a-b
A rabbinic enactment validating transfer of funds, without moving the actual acquired item, as a means of acquiring one's share in an Eruv meal: Eruvin 81a-b
Transporting through a yard if the adjacent residents already merged with residents of adjacent yards in a large alley: Eruvin 67b-68a, 71b-72a
Transporting through an alley if the adjacent residents already merged as residents of a yard: Eruvin 71b-72a, 73a-b
Requiring residents to merge both as far as their yard as well as the larger alley, lest the young forget about the issue of merging yard: Eruvin 73b
Merging alley ownership is about permission and rights; merging yards is about establishing residence in the yard: Eruvin 71b-72a
Status of the period of "Bein haShemashot [Between the suns; sunset]" as far as an Eruv meal which is established or destroyed during that period, at the start of Shabbat: Eruvin 76a
What happens if new residents are established on Shabbat: Eruvin 69b-71a, 79b
Materials
Gauging the required amount of sandwich material or non-sandwich material [for shitufei mevo'ot]: Eruvin 29b-30a
Using a fragment, as opposed to a whole loaf [for eruvei chatzeirot, and possible for shitufei mevo'ot as well]: Eruvin 80b-81a
Using a loaf of bread which is composed of pieces attached to each other with a splinter: Eruvin 81a
Using a loaf from which a piece was removed for the dough tithe: Eruvin 81a