[14] J. Zou et al. Towards visible-wavelength passively mode-locked lasers in all-fibre format. Light Sci. Appl., 9, 61(2020).
[17] J. Nakanishi et al. Watt-order direct green laser oscillation at 522 nm in Pr3+-doped waterproof fluoro-aluminate-glass fiber, JTu4A.02(2013).