WASET
    Mohsen Zahraei,  Some Results on the Generalized Higher Rank Numerical Ranges.   journal   = {International Journal of Mathematical and Computational Sciences}, [online]. World Academy of Science, Engineering and Technology.
    August 2015, vol. 104(8). 489 - 493
    [viewed 20 April 2024]. Available from: https://publications.waset.org/pdf/10002343.