For racial spells in the Advanced Race Guide and Inner Sea Races, the Additional Resources document is fairly clear on how legality works: "...racial spells are only available for characters of the associated race".

However, most of the race-specific player companion books, such as Dwarves of Golarion and Orcs of Golarion, do not have such a restriction listed in the AR (with the notable exception of Goblins of Golarion, which restricts all content to the handful of legal goblin characters).

Am I correct, then, that any character could learn ablative sphere (from Humans of Golarion), illusory poison (from Gnomes of Golarion), or vigor (from Orcs of Golarion), keeping in mind the source ownership requirements of the AR?