@article{PismaZhETF.9.590,
    title = {Acoustic Birefringence in Antiferromagnetic $MnCO_2$},
    author = {Gakel', V. R.},
    journal = {πΙΣΨΝΑ Χ φότζ},
    volume = {9},
    issue = {10},
    pages = {590},
    year = {1969},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_25406.shtml},
}