I am looking for a grammar that describes the formal language
$L = \{ xyx^R \;|\; x,y \in \{a,b\}^*\}$
where $\{a,b\}^*$ corresponds to the regular expression [ab]*.
If there would be no y and the language would therefore contain all the words that are palindromes there wouldn't be any problem. I just don't get the "y" included therein.
Could you please help me to find a solution?
Thanks in advance