The Walters Art Museum, Board of Trustees (official website)

This is the museum's own current statement of its governing board, self-published on its own website rather than independent scholarship. For a fact of exactly this shape, who legally holds and governs the institution, self-report from the institution itself is ordinary and reliable practice: a museum's corporate governance is a matter of public record it has no incentive to misstate, unlike a claim about its collection's history or attribution, where self-interest can run the other way. It is the right source for the plain organizational fact it states and for nothing beyond it; a claim about the museum's history, acquisitions or scholarly standing needs a dedicated outside source.