If you were born on Thursday, December 31, 1942 then How Deep Is Your Love by The Bee Gees was the number one on your 35th birthday, and went to number one on December 18, 1977. Check the price of How Deep Is Your Love by The Bee Gees on Amazon.com
The biggest selling book of 1977 (the year you turned 35) was The Silmarillion by J.R.R. Tolkien and Christopher Tolkien.