1. Aka Get al 1996a inOSA TOPS on advanced solid state lasers (eds) S A Payne and C R Pollock (Washington DC: Optical Society of America) Vol.1
2. Aka G, Kahn-Harari A, Vivien D, Salin F, Godard J and Benitez J M 1996Eur. J. Solid State Inorg. Chem. 33 727
3. Chen C, Wu B, Jiang A and You G 1984Sci. Sin. B7 579
4. Chen C, Wu Y, Jiang A, Wu B, You G, Li R and Lin S 1989J. Opt. Soc. Am. B6 616
5. Iwai M, Kobayashi T, Furuya H, Mori Y and Sasaki T 1997Jpn J. Appl. Phys. 36 276