Endogenous Growth on Tin-Pan Alley

I was talking to a class about the growth of knowledge, and the trade-off , in protecting intellectual property, between creating incentives for new discoveries, and  maximizing the effect of new knowledge as input for further knowledge. As an example of this last, "standing-on-shoulders" effect, I mentioned the astonishing number of great jazz compositions that have been based on the chord changes of "I Got Rhythm." But instead of attributing the song to Gershwin, correctly, or even to Irving Berlin, who is at least a songwriter, I attributed it to ISAIAH Berlin. Oy! You don't know about Berlin's residence on Tin-Pan Alley? Well, who do you think wrote

Two Concepts of Blue Skies
A Pretty Girl is Like a Hedgehog - Unless She's Like a Fox
Alexander Herzen's  Ragtag Band,

inter alia?