@misc{S._Majumder_On,
 author={S. Majumder and R. Mandal},
 address={Երևան},
 howpublished={online},
 publisher={Հայաստանի ԳԱԱ},
 type={Հոդված},
 title={On an open problem of Zhang and Xu},
 keywords={Mathematics, Science},
}