1. M. Poláček and W. Siegel, Natural curvature for manifest T-duality, JHEP 01 (2014) 026 [ arXiv:1308.6350 ] [ INSPIRE ].
2. W. Siegel, Two vierbein formalism for string inspired axionic gravity, Phys. Rev. D 47 (1993) 5453 [ hep-th/9302036 ] [ INSPIRE ].
3. W. Siegel, Superspace duality in low-energy superstrings, Phys. Rev. D 48 (1993) 2826 [ hep-th/9305073 ] [ INSPIRE ].
4. W. Siegel, Manifest duality in low-energy superstrings, in Berkeley 1993, Proceedings, Strings ‘93, M.B. Halpern et al. eds., World Scientific, Singapore (1995) hep-th/9308133 [ INSPIRE ].
5. M. Hatsuda and K. Kamimura, Classical AdS superstring mechanics, Nucl. Phys. B 611 (2001) 77 [ hep-th/0106202 ] [ INSPIRE ].