My question involves a traffic ticket from the state of: California

As soon I have entered the high way, I drove at the minimum speed limit which is at 50-55. A few cars passed by me as I entered traffic but then moments later, the police offer had signaled me to pull over. I had only been in the highway for less than a minute long ! The cop pulled me over while he was driving, but he was not parked out somewhere where he can catch my slow driving speeds. No siren was used but his lights was turned on indicating me to pull over though. He told me that I was way under the speed limit and has given me a citation for impeding traffic and other things I have forgotten. He did forget to write down the what my speed limit was and the approx. speed limit on the ticket. How will the judge even know what speed limit posted was if the police offer didn't write it down? Can I fight this ticket and have a chance to win because theirs no proof on the ticket for the judge to know the speed limit. Also, I was on the right lane.