1. Singapore Synchrotron Light Source, National University of Singapore, 5 Research Link, Singapore 117603
2. Photothermal Spectroscopy Corp., 325 Chapala Street, Santa Barbara, California 93101, United States
3. Forensic Division, Criminal Investigation Department, Police Cantonment Complex 391, New Bridge Road 20-04, CID Tower Block C, Singapore 088762
4. Physics Department, National University of Singapore, 2 Science Drive 3, Singapore 117542