IT return of resident with salary income from singapore

An assessee is having salary income from 10 months in India. For remaining 2 months, he has earned salary income from Singapore. As he is resident in India, how the same should be reflected in his Indian ITR. Also, calendar year is followed in Singapore for tax filings and in India it is April to March. So how to claim tax credit ( currently we aren't aware if the salary is taxable in Singapore or not and if any taxes are paid.)