Kołodziej JA, Uściłowska A. Trefftz-type procedure for Laplace equation on domains with circular holes, circular inclusions, corners, slits, and symmetry. CAMES. 2023;4(3-4):501-519. Accessed January 12, 2025. https://cames3.ippt.pan.pl/index.php/cames/article/view/1386