@article{Grytczuk:2005,
  author  = "A. Grytczuk and J. Grytczuk",
  title   = "Some Results Connected with the Class Number problem in Real Quadratic Fields",
  journal = "Acta Mathematica Sinica, English Series",
  volume  = "Vol. 21",
  number  = "no 5",
  pages   = "1107--1112",
  year    = "2005",
}