Chen later obtained a Doctor of Musical Arts degree from the University of Michigan.

He obtained a Doctor of Science Degree in Engineering Management.

Graduate students can obtain a Doctor of Education (Ed.

He later obtained a Doctor of Veterinary Medicine degree from Washington State University.

Berloco obtained a Doctor of Theology degree and a Licentiate in Canon law.

He obtained a Doctor of Philosophy degree from the Sorbonne.

He later obtained a Doctor of Civil Law.

In 1994 he obtained a Doctor of Science in cell biology and medicine.

Natalegawa also obtained a Doctor of Philosophy at the Australian National University in 1993.

Brain obtained a Doctor of Ministry degree from Fuller Theological Seminary.