Almost r-contact structures
Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Série 3, Tome 26 (1972) no. 1, p. 97-115 
@article{ASNSP_1972_3_26_1_97_0,
     author = {Van\v zura, Ji\v r\'\i },
     title = {Almost $r$-contact structures},
     journal = {Annali della Scuola Normale Superiore di Pisa - Classe di Scienze},
     publisher = {Scuola normale superiore},
     volume = {Ser. 3, 26},
     number = {1},
     year = {1972},
     pages = {97-115},
     zbl = {0234.53040},
     mrnumber = {362132},
     language = {en},
     url = {http://www.numdam.org/item/ASNSP_1972_3_26_1_97_0}
}

Vanžura, Jiří. Almost $r$-contact structures. Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Série 3, Tome 26 (1972) no. 1, pp. 97-115. http://www.numdam.org/item/ASNSP_1972_3_26_1_97_0/

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