[1] KRÁL J.: The Fredholm method in potential theory. Trans. Amer. Math. Soc. 125 (1966), 511-547. MR 0209503

[2] KRÁL J.: Flows of heat and Fourier problem. Czech. Math. Journ. 20 (1970), 550 - 598. MR 0271554

[3] Sapožnikova V. D.: Rešenije treťej krajevoj zadači metodami teorii potenciala dlja oblastej s nereguljarnymi granicami. Problemy Mat. Analiza, Izd. Leningradskogo un., 1966. MR 0213597