Fighting with incorporeal - Pathfinder

[Daozi]

Ladies and Gentleman,

To make a long story short: Pathfinder, 7th lev. party consist of: Zealot (tank), Barbarian (DPS), Rogueish (mix of classes; stealth & DPS), Cleric, Arcanist and Bard (me).
Two various incorporeals that we'll have to fight separately. One is lurking in the shadows (so Daylight may be useful), another... is not. Both may escape from the fight and, presumably, they will.
My question is: how to prevent them from escaping? We have the Shadow Trap spell, but a shadow doesn't have it's own shadow so this may be tricky here. Zealot can provide us with the ghost touch weapons, cleric with protection from evil (one of these guys can possess living beings). Ghostbane Dirge, Magic Missiles, Chain of Perdition, Mage Armor - we can have those, but still: both guys can just enter the nearest wall and that'll be it. And we have to eliminate them, at least from our plane :)

(I have checked various threads but couldn't find answer for escaping problem, just how to fight with incorporeal, but this I already know).

Thanks in advance for any advices!

[tyckspoon]

Incorporeal creatures do not tend to be blessed with an abundance of hitpoints; alpha-striking them may be all you need.

Just from what you've listed, I see two possibilities, but you'll need to get a ruling from your DM because they're not explicit in the text.

Ghostbane Dirge forces the subject into a 'semi physical' state. Although the explicit effect of this is making them more vulnerable to getting hit with weapons, it should reasonably also stop them from trying to pass through walls, as they are now in a form that interacts with physical reality.

Chain of Perdition creates an object of physical force. It can use the Entangle Dirty Trick or grapple the incorporeal creatures. How does that work? Does the Chain physically wrap itself around the subject? If so, the incorporeal creature is now dragging around a corporeal object, and would have to find a way to free itself from the entanglement or beat the grapple before it could try to move through a solid barrier.

[Batcathat]

Do you think they'll come to you or do you have to go to them? If it's the former, you could try to pick a site that favors you more than them. Though to be honest I'm not sure what that might be. A big open area, maybe? But I suppose they could still sink into the ground.

[Heavenblade]

Maybe a ghost touch net will do? They are covered in it, and they can't move with it through walls...same goes for manacles, or your friendly neigbourhood grappler

[Daozi]

Well, we know where exactly they are. One in the temple's crypt (so he can easily evade us), but he is preying in the city in his free time. Another one in some kind of ruins (sounds very original isn't it? :D) - this one is bounded to the place, but in fact it / he is bounded to the whole village under which the ruins are located. So both can easily escape. Grappling, correct me if I'm wrong, would be possible only if ghostbane dirge worked. But one, presumably, have high will save and another one surely has it's will save really good.
Or is there a method to become incorporeal and then grapple him, which I'm not aware of? But the method on 7th level?