"décédé...: A San-Francisco, Richard Mulder, né à Amsterdam, en 1823, pianiste, compositeur, chef d’orchestre, fixé depuis plusieurs années aux États-Unis. Il avait épousé, en 1844, Mlle Lia Duport, qui, de bonne heure, a brillé comme cantatrice et s'est ensuite vouée au professorat..."
One does find oneself wondering if this is necessarily the same Richard Mulder whose works were published by Brandus
and Jacques Maho
(there are some opus number conflicts, for example, but since opus numbers were assigned by publishers for many composers - consider Dvořák's troubles with Simrock just as a single for-instance-... this does not surprise), but Fétis provides those works in his worklist and while his biography was written after the composer's death (which he dates to 22 December, contrary to the contemporary obituary from the New York Times), one assumes he may have had some reason other than the sameness of names.