@article{PismaZhETF.48.457,
    title = {Energy gap in $YBa_2Cu_3O_{7-x}$ single crystals with various oxygen concentrations},
    author = {Volodin, A. P. and Kotyuzhanskii, B. Ya. and Stepanyan, G. A.},
    journal = {πΙΣΨΝΑ Χ φότζ},
    volume = {48},
    issue = {8},
    pages = {457},
    year = {1988},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_16766.shtml},
}