Here are some books that you may be interested in.
Carry the Spices - Singaporean Doctors in Medical Missions and Pastoral Ministry
This book is a collection of 28 essays by 24 Singaporean medical doctors and dental surgeons whom the Lord has called to carry “spices” to the communities both locally and beyond. These professionals learnt that the obstacles and challenges in healthcare in poverty-stricken regions are immense and the issues complex but found that God asked them only to be faithful and obedient – to carry the “spices” and He will remove the obstacles. So they went to serve in Africa, East Asia, Central and South Asia, South-East Asia and Singapore.