Which number one song contains in its lyrics the title of record which succeeded it?

The answer is "Do You Love Me" by The Contours. The song contains in its lyrics the title of the song that succeeded it at the top of the Billboard Hot 100 chart, "Please Mr. Postman" by The Marvelettes. The lyrics include the line, "Do you love me / Like you say you love me / Like I love you in 'Please Mr. Postman'."