The note in References ("Dickerson gives a date for this rose of circa 1844 and in the same entry he says 'Dembrowski' (of 1840) is one of its offspring") appears to betray the fact that whoever wrote the References note didn't read the full quote. What Dickerson (me!) actually says, fully, is "The Hybrid Bourbon 'Dembrowski' (Vibert 1840) sported from this; presumably the introduction of 'Pope' thus predates 1840 (unless for one reason or another Vibert had pre-release specimens of 'Pope'; Laffay is known to have bought propagation rights to Vibert's unreleased seedlings upon occasion." It's important to give remarks in their full context.