40 But let the unions in question draw their vital force from principles of wholesome liberty; let them take their form from them, take their form from the lofty rules of justice and of honesty and, conforming themselves to those norms, let them act in such a manner that in their care for the interests of their class they violate no one's rights; let them continue to strive for harmony and respect the common weal of civil society.
Source: Sertum Laetitiae (Vatican.va)