Photonic Microresonator Research and Applications. SpringerSeriesinOpticalSciences 156. Boston, MA: Springer US. 2010. ISBN 9781441917430. doi:10.1007/978-1-4419-1744-7
Society of London. Series A. Mathematical and physical sciences 397th. 1985: 184. Proceedings of the Royal Society of London. Series A. Mathematical and