Berkovich, Yakov and Janko, Zvonimir. "§83. p-groups G with Ω2(G) or Ω2*(G) extraspecial". Volume 2, Berlin, New York: De Gruyter, 2008, pp. 396-398. https://doi.org/10.1515/9783110208238.396
Berkovich, Y. & Janko, Z. (2008). §83. p-groups G with Ω2(G) or Ω2*(G) extraspecial. In Volume 2 (pp. 396-398). Berlin, New York: De Gruyter. https://doi.org/10.1515/9783110208238.396
Berkovich, Y. and Janko, Z. 2008. §83. p-groups G with Ω2(G) or Ω2*(G) extraspecial. Volume 2. Berlin, New York: De Gruyter, pp. 396-398. https://doi.org/10.1515/9783110208238.396
Berkovich, Yakov and Janko, Zvonimir. "§83. p-groups G with Ω2(G) or Ω2*(G) extraspecial" In Volume 2, 396-398. Berlin, New York: De Gruyter, 2008. https://doi.org/10.1515/9783110208238.396
Berkovich Y, Janko Z. §83. p-groups G with Ω2(G) or Ω2*(G) extraspecial. In: Volume 2. Berlin, New York: De Gruyter; 2008. p.396-398. https://doi.org/10.1515/9783110208238.396