Pearson's Encyclopedia of Roses (1956), pg. 172.

Bonn (Hybrid Musk)
(Hamburg X Independence)
Large, semi-double, orange-scarlet blooms. Fragrant. Makes a fine shrub or 6 ft. hedge if lightly pruned.
(Kordes, 1949).

Introduced by the Wheatcroft Brothers

NRS Annual 1951 p70

Walking around the city of Bonn I have seen one rose that was not familiar to me in a couple of gardens, and in the public green. I can't remember to have seen it anywhere else though. I've started wondering whether it could be 'Bonn'? It would make perfect sense ... I'll include photos made on a wet day.