@article{PismaZhETF.88.454,
    title = {Evolution of spin entanglement and an entanglement witness in multiple-quantum NMR experiments},
    author = {Fel'dman, E. B. and Pyrkov, A. N.},
    journal = {πΙΣΨΝΑ Χ φότζ},
    volume = {88},
    issue = {6},
    pages = {454},
    year = {2008},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_28245.shtml},
}