Magus Spell Combat and Casting non-Magus Slots

[Quandary]

Spell Combat says " As a full-round action, he can make all of his attacks... and can also cast any spell from the magus spell list with a casting time of 1 standard action"

So as long as it is also on the magus list, can this be using another class' spell slots? What about SLAs?
Or is it supposed to be Magus spell slots only? And Broad Study would allow casting using another class' spell slots? (what about SLAs?)

[Tholomyes]

RAW seems pretty clear to me to mean if it's "from the magus spell list with a casting time of 1 standard action" without specifying if it's a magus spell slot. SLAs however wouldn't, since they're not spells but SLAs.

I don't believe by RAI, (I may be wrong, though) that it's supposed to work like that, and Broad Study would be required to allow that.

[Xaratherus]

I agree with Tholomyes' first statement, disagree with the second. The wording of Broad Study (to me) indicates it allows the magus to cast a greater range of spells with Spell Combat; I would allow the former without requiring Broad Study.

[LazarX]

Broad Study only allows what it specifically allows, the use of another classes spells for spell combat. Nothing less, nothing more.