taget the origin of a spell RAW?

[0-hr]

Reposting since the other thread got sidetracked. I was recently told:

the dispelling of a single spell requires you to target the spells point of origin (the spell itself, not the caster) and since the point of origin for the spell effect on a summoned creature is the summoned creature itself a targeted dispel will negate the spell with respect to only the creature targeted.
...
These are merely the rules as written.

I'd like to read the text about having to target the origin of a spell, and also the part about the point of origin of a summons moving with the creature summoned. Could someone point me to the text where this is discussed?

 

[Infiniti2000]

Unfortunately, it's just not explicitly written anywhere that to target a spell you must target its point of origin. The area dispel magic requires it, however, so the debate is highly in favor of that interpretation.

 

[Caliban]

Here's the last big discussion. I don't think it was ever really resolved.

http://www.enworld.org/showthread.php?t=158078