There are actually many books you can refer to. Errorless is a pretty good book and has kept a really good standard over the years. But the content in errorless is extensive. So if you're referring it, make sure you're only studying the MHT-CET 2018 portion from it.
You can even refer to NCERT books for PCMB. It has exhaustive data which is really simple to understand and comprehend.
Other publications like Marvel, Objective, Target also provide really good books with a lot of practise questions and solved papers for CET.
It would be best if you any of refer these books and your HSC textbooks. Most of the CET syllabus would be based on your textbook itself. You have ample time till MHT-CET 2018. So pick one of these and get going.
Good Luck!
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