CYCLIZATION OF THE SUBSTITUTED N-(ORTHO-CYCLOPROPYLPHENYL)-N′-ARYL UREAS AND THIOUREAS IN THE GAS PHASE AND SOLUTION ArticleLobodin V.V., Fedotov A.N., Dem'yanov P.I., Lebedev A.T., Ovcharenko V.V., Pihlaja K., Blumenthal T.Journal of The American Society for Mass Spectrometry. Том 16. 2005. С. 1739-1749