Watch your "which"

Here's an irresistible sentence from the Metropolitan Museum of Art's description of a Louis Comfort Tiffany chair:

This chair is one of a pair closely related to a suite of furniture from the music room of the H. O. Havemeyer house, which Tiffany designed with Samuel Colman in 1891-92.

Now "which" of the bolded nouns did Tiffany and Colman design? We can almost definitely rule out "this chair"; but that still leaves four possible antecedents for that put-upon relative pronoun.