| Fixed point theory and applications RP Agarwal, M Meehan, D O'regan Cambridge university press, 2001 | 1499 | 2001 |
| Positive solutions of differential, difference and integral equations RP Agarwal, D O'Regan, PJY Wong Springer Science & Business Media, 2013 | 1008 | 2013 |
| Dynamic equations on time scales: a survey R Agarwal, M Bohner, D o'Regan, A Peterson Journal of Computational and Applied Mathematics 141 (1-2), 1-26, 2002 | 868 | 2002 |
| Iterative construction of fixed points of nearly asymptotically nonexpansive mappings RP Agarwal, D O Regan, DR Sahu Journal of Nonlinear and convex Analysis 8 (1), 61, 2007 | 844 | 2007 |
| Oscillation theory for difference and functional differential equations RP Agarwal, SR Grace, D O'Regan Springer Science & Business Media, 2013 | 821 | 2013 |
| Generalized contractions in partially ordered metric spaces RP Agarwal, MA El-Gebeily, D O'Regan Applicable Analysis 87 (1), 109-116, 2008 | 817 | 2008 |
| Fixed point theory for Lipschitzian-type mappings with applications RP Agarwal, D O'Regan, DR Sahu Springer 6, x+ 368, 2009 | 791 | 2009 |
| Infinite interval problems for differential, difference and integral equations RP Agarwal, D O'Regan Springer Science & Business Media, 2012 | 563 | 2012 |
| On a new class of abstract impulsive differential equations E Hernández, D O’Regan Proceedings of the American Mathematical Society 141 (5), 1641-1649, 2013 | 543 | 2013 |
| Variational approach to impulsive differential equations JJ Nieto, D O’Regan Nonlinear Analysis: Real World Applications 10 (2), 680-690, 2009 | 527 | 2009 |
| Oscillation theory for second order linear, half-linear, superlinear and sublinear dynamic equations RP Agarwal, SR Grace, D O'Regan Springer Science & Business Media, 2013 | 465 | 2013 |
| Fixed point theorems for generalized contractions in ordered metric spaces D O'Regan, A Petruşel Journal of Mathematical Analysis and Applications 341 (2), 1241-1252, 2008 | 465 | 2008 |
| Theory of singular boundary value problems D O'regan World Scientific, 1994 | 417 | 1994 |
| Oscillation criteria for second-order nonlinear neutral delay dynamic equations RP Agarwal, D O'Regan, SH Saker Journal of Mathematical Analysis and Applications 300 (1), 203-217, 2004 | 356 | 2004 |
| Positive solutions for Dirichlet problems of singular nonlinear fractional differential equations RP Agarwal, D O'Regan, S Staněk Journal of Mathematical Analysis and Applications 371 (1), 57-68, 2010 | 324 | 2010 |
| Existence theory for nonlinear integral and integrodifferential equations D O'Regan, M Meehan Springer Science & Business Media, 2012 | 313 | 2012 |
| Existence theory for nonlinear ordinary differential equations D O'Regan Springer Science & Business Media, 1997 | 290 | 1997 |
| On recent developments in the theory of abstract differential equations with fractional derivatives E Hernández, D O’Regan, K Balachandran Nonlinear Analysis: Theory, Methods & Applications 73 (10), 3462-3471, 2010 | 275 | 2010 |
| Existence of solutions for semi-linear abstract differential equations with not instantaneous impulses M Pierri, D O’Regan, V Rolnik Applied Mathematics and Computation 219 (12), 6743-6749, 2013 | 262 | 2013 |
| Oscillation theory for second order dynamic equations RP Agarwal, SR Grace, D O'Regan CRC Press, 2002 | 252 | 2002 |
