@article{etna_vol46_pp55-70,
  author  = {Drahoslava Janovsk\'a and Gerhard Opfer},
  title   = {The number of zeros of unilateral polynomials over coquaternions and related algebras},
  journal = {Electron. Trans. Numer. Anal.},
  volume  = {46},
  year    = {2017},
  pages   = {55--70},
}