Expert on French music publishers?

[4candles]

Might anyone here know of an expert on French music publishers? My query is more specifically about those active in the latter half of the 19th century.

Many thanks.

[Alan Howe]

That's a pretty wide field. Could you be more specific, please?

[4candles]

Jacques Maho / Julien Hamelle.

I'm interested in the Maho music estate as it was when bought by Hamelle in 1877, and, separately, the Hamelle music estate around 1876-78. Not just published catalogues, but also items in manuscript.