no. 1
The Cauchy problem for a nonlinear Wheeler-DeWitt equation
Annales de l'I.H.P. Analyse non linéaire, Tome 10 (1993) no. 1, pp. 99-107. 
@article{AIHPC_1993__10_1_99_0,
     author = {Dias, J.-P. and Figueira, M.},
     title = {The {Cauchy} problem for a nonlinear {Wheeler-DeWitt} equation},
     journal = {Annales de l'I.H.P. Analyse non lin\'eaire},
     pages = {99--107},
     publisher = {Gauthier-Villars},
     volume = {10},
     number = {1},
     year = {1993},
     mrnumber = {1212630},
     zbl = {0790.35074},
     language = {en},
     url = {http://www.numdam.org/item/AIHPC_1993__10_1_99_0/}
}
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Dias, J.-P.; Figueira, M. The Cauchy problem for a nonlinear Wheeler-DeWitt equation. Annales de l'I.H.P. Analyse non linéaire, Tome 10 (1993) no. 1, pp. 99-107. http://www.numdam.org/item/AIHPC_1993__10_1_99_0/

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