All articles in this issue include authors from 8 countries of origin (Indonesia, China, Netherlands, Malaysia, Brunei Darussalam, Nigeria, Egypt, and Singapore).

All articles in this issue include authors from 4 countries of origin (Indonesia, Malaysia, Egypt, and Russia).

All articles in this issue include authors from 4 countries of origin (Indonesia, Malaysia, Saudi Arabia, and Cambodia).

All articles in this issue include authors from 4 countries of origin (India, Malaysia, Indonesia, and Nigeria).

All articles in this issue include authors from 3 countries of origin (Indonesia, Malaysia, and Netherlands).