The following is Open Game Content from a 3PP Source

ELEMENTAL WIZARD SPELLS

Sorcerer/Wizard spells not included in this list are not considered to be elemental spells. Those spells can still be learned by an elemental wizard though, just as any sorcerer/wizard can learn those spells, so long as the spells are not from his opposition element. Also, note that some spells are considered to belong to more than one element due to the way the spell works or the composition of the effects. An elemental wizard can cast a spell that belongs to his element as well as his opposing element with no penalty.

There are also a handful of spells that are classified as Universal Element spells, which are elemental spells that any elemental wizard can learn, no matter what his element of opposition is (though there may be some restrictions on what the wizard can do with the spell).