Öztürk Mert, RukiyeYılmaz, BülentIsmailov, Zameddin I.2019-05-132019-05-132018Öztürk Mert, Rukiye, Yılmaz, B., İsmailov, Z. İ. (2018). First order self-adjoint multipoint quasi-differential operators. Turkish Journal of Mathematics, 42(4), 2071-2079.1300-0098https://doi.org/10.3906/mat-1803-136https://hdl.handle.net/11491/1314In this paper, using the Calkin-Gorbachuk method, the general form of all self-adjoint operators generated by first order linear singular multipoint quasi-differential expressions in the direct sum of weighted Hilbert spaces of vector functions has been found. Later on, the geometry of the spectrum set of these type extensions was researched. ©TÜBITAK.eninfo:eu-repo/semantics/openAccessDeficiency IndicesMultipoint Quasi-Differential ExpressionSelfadjoint OperatorsSpectrumArticle4242071207910.3906/mat-1803-136N/AQ2