On 3 October, 1529 the Marburg Colloquy ended and the attendees signed the 15 Marburg Articles. On 14 there was decisive agreement. On the 15th, hardly any. Naturally the 15th was the article on the Lord’s Supper. You can download a copy of the Articles (which I’ve been unable to locate anywhere online, surprisingly) at the link above.
By the way- Zwingli was right about the meaning of the Supper and Luther and his partisans were wrong. Still are.