no. 1
The simplified Wheeler-Dewitt equation : the Cauchy problem and some spectral properties
Annales de l'I.H.P. Physique théorique, Tome 54 (1991) no. 1, pp. 17-26. 
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     author = {Dias, Jo\~ao-Paulo and Figueira, M\'ario},
     title = {The simplified {Wheeler-Dewitt} equation : the {Cauchy} problem and some spectral properties},
     journal = {Annales de l'I.H.P. Physique th\'eorique},
     pages = {17--26},
     publisher = {Gauthier-Villars},
     volume = {54},
     number = {1},
     year = {1991},
     mrnumber = {1102969},
     zbl = {0741.35034},
     language = {en},
     url = {http://www.numdam.org/item/AIHPA_1991__54_1_17_0/}
}
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Dias, João-Paulo; Figueira, Mário. The simplified Wheeler-Dewitt equation : the Cauchy problem and some spectral properties. Annales de l'I.H.P. Physique théorique, Tome 54 (1991) no. 1, pp. 17-26. http://www.numdam.org/item/AIHPA_1991__54_1_17_0/

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