Conversation so far:
who were the rock and roll trio?
In 1952, the Burnette brothers and their friend Paul Burlison formed a group called the Rhythm Rangers which was eventually renamed the Rock and Roll Trio.
when was the Rock and Roll trio formed?
In 1952, the Burnette brothers and their friend Paul Burlison formed a group called the Rhythm Rangers which was eventually renamed the Rock and Roll Trio.

Question: what was the name of the group they formed?
Self-contained rewrite: what was the name of the group they formed?