Rad, N.
(2016).
 A note on the P - Center problem.
<em>Yugoslav Journal Of Operations Research, 21</em>(2).
Retrieved from <a href="https://yujor.fon.bg.ac.rs/index.php/yujor/article/view/374" target="_new">https://yujor.fon.bg.ac.rs/index.php/yujor/article/view/374</a>