BARTUŠEK, Miroslav a John R. GRAEF. Limit-point/limit-circle results for forced second order differential equations. Dynamic systems and applications. 2015, roč. 10, č. 1, s. 11-26. ISSN 0973-5321.
BARTUŠEK, Miroslav a John R. GRAEF. Strong nonlinear limit-point/limit-circle properties for a class of fourth order equations. Commun. Appl.Anal. 2008, roč. 11, č. 4, s. 469-484. ISSN 1083-2564.