Fy 2017-18 individual only salary income 9 months india salary and 3 months turkey salary

My client is regular Salary Return filer ITR 1, In FY 2017-18 his 9 months Salary from India Chennai based company and his company depute him to Turkey as representative which he has received 3 months Turkey salary deduction of Turkey Income Tax and Stamp Duty.    In AY 2018-19 which ITR form I have to file and how to file online Form 67.    Whether Form 67 to be file before ITR submission.   Guide me, favourable reply awaited.