[1] Krishnan P, Alexander J D, Butler B J, et al. Soil Sci. Soc. Am. J., 1980, 44: 1282.

[2] Dalai R C, Henry R J. Soil Sci. Soc. Am. J., 1986, 50: 120.

[5] Cheng Wenchang, Laird D A, Mausbach M J, et al. Soil Sci. Soc. Am. J., 2001, 65: 480.

[6] Cheng Wenchang, Laird D A. Soil Science, 2002, 167: 110.

[8] McCarty G W, Reeves J B, Reeves V B, et al. Soil Sci. Soc. Am. J., 2002, 66: 640.

[9] Malley D F, Yesmin L, Wray D, et al. Communications in Soil Science and Plant Analysis, 1999, 30: 999.

[10] Malley D F, Yesmin L, Eilers R G. Soil Sci. Soc. Am. J., 2002, 66: 1677.

[12] Li Minzan. Proceedings of SPIE, 2005, 5881: 1.

[13] Cozzolino D, Moron A. Soil & Tillage Research, 2006, 85: 78.

[14] Mouazen M, Karoui R, Baerdemaeker J D, et al. Soil Sci. Soc. Am. J., 2006, 70: 1295.

[15] Kooistra L, Wehrens R, Leuven R S, et al. Analytica Chimica Acta, 2001, 446: 97.