Which institute is best for doing MBA through correspondence course in 1 Year? ?

I am a B.Sc graduate with 13 years of work experience in Quality Assurance department in Automobile industry. I want to do MBA in operation management with specialization in Total Quality Management. There are institutes which offer MBA in 1 Year with 5 subjects. Are these MBA degrees are valid? Suggest me suitable institute which offers MBA in Operation management through correspondence course.