@misc{Wąsik_Jacek_Sport_2013,
 author={Wąsik, Jacek and Willy, Pieter},
 type={artykuł},
 publisher={Projack},
 title={Sport sparring concept in taekwon-do - The Christmas tree diagram},
 address={Częstochowa},
 year={2013},
 language={eng},
}