WASET
    Mikko Löytynoja and  Nedeljko Cvejic and  Tapio Seppänen,  Watermark-based Counter for Restricting Digital Audio Consumption.   journal   = {International Journal of Computer and Information Engineering}, [online]. World Academy of Science, Engineering and Technology.
    July 2007, vol. 7(7). 2275 - 2279
    [viewed 27 April 2024]. Available from: https://publications.waset.org/pdf/2896.