I have several hundred files with file names such as:
 20110404\_091415-R1-sometext

Another file name might be named:
 20110404\_091415-R1.2-sometext

What I would like to do is use the Unix grep tool in the terminal to find files that start with 2011 and also contain -R1 within the file name. Unfortunately, I have no idea to find files that satisfy both these criteria. I have tried to figure out a regex that would match this, but I am only a beginner programmer. Can anyone help please? Thanks in advance for your time.