1. 1) D. Tanase and Z. Xue: Journal of MMIJ, 124 (2008), 50-60.
2. 2) O. Eiken: IEA Monitoring and Verification Workshop (Santa Cruz, November, 2004).
3. 3) D. White: IEA Monitoring and Verification Workshop (Santa Cruz, November, 2004).
4. 5) J. Harris, R. Nolen-Hoeksema, R. Langan, M. Schaack, S. Lazaratos, and J. Rector III: Geophysics, 60 (1995), 667-681.