(19) The Beurling-Lax-Halmos Theorem for infinite multipliity (with R.E. Curto and I.S. Hwang)
J. Funct. Anal. (2021), Art. ID 108884, 101 pp. 20JFApdf
(18) Matrix functions of bounded type: An interplay between function theory and operator theory (with R.E. Curto and I.S. Hwang)
Memoirs of Amer. Math. Soc. 260 (2019), No. 1253, x+100 pp. Mams19.pdf
(17) Subnormal and quasinormal Toeplitz operators wth matrix-valued rational symbols (with R.E. Curto, I.S. Hwang and D. Kang)
Adv. Math. 255 (2014), 561-585, 14AIM.pdf
(16) Hyponormality of bounded-type Toeplitz opertors (with R.E. Curto amd I.S. Hwang)
Math. Nach. 287(11/12)(2014), 1207-1222 , 14MN.pdf
(15) Hyponormal Toeplitz operators with matrix-valued circulant symbols (with I.S. Hwang and D. Kang)
Complex Anal. Oper. Theory 7(2013), 843-861, 13 CAOT.pdf
(14) Which subnormal Toeplitz operators are either normal or analytic? (with R.E. Curto and I.S. Hwang)
J. Funct. Anal. 263(8)(2012), 2333-2354, 12JFA.pdf
(13) Hyponormality and subnormality of block Toepltz operators (with R.E. Curto and I.S. Hwang)
Adv. Math. 230 (2012), 2094-2151, 12AIM.pdf
(12) A criterion on the hyponormality of Toeplitz opeorators with polynomial symbols via Schur numbers (with D. Kang)
Linear Alg. & Appl. 436 (2012), 3608-3617, 12LAA.pdf
(11) A Gap between hyponormality and subnormality for block Toeplitz operators (with I.S. Hwang and D. Kang)
J. Math. Anal. Appl. 382(2011), 883-891, 11-1JMAA.pdf
(10) Hyponormality of Toeplitz operators with rational symbols (with I.S. Hwang)
Math. Ann. 335 (2006), 405-414 06HL1.pdf
(9) Cowen sets for Toeplitz operators with finite rank selfcommutators
J. Operator Theory 54(2)(2005), 301-307 05L1.pdf
(8) Hyponormality of trigonometric Toeplitz operators (with I.S. Hwang)
Trans. Amer. Math. Soc. 354 (2002), 2461-2474 HL2.pdf
(7) Triangular Toeplitz contractions and Cowen's sets for analytic polynomials (with C. Muneo and R.E. Curto)
Proc. Amer. Math. Soc. 130 (2002), 3597-3604, CCL.pdf
(6) Joint hyponormality of Toeplitz pairs (with R.E. Curto)
Memoirs of Amer. Math. Soc. 150 (2001), No. 712, x+65 pp. Mams01.pdf
(5) Reduced Cowen sets (with R.E. Curto)
New York J. Math. 7 (2001), 217-222, CuLe5.pdf
(4) Hyponormality of Toeplitz operators with polynomial symbols: An extremal case (with I.H. Kim and I.S. Hwang)
Math. Nach. 231 (2001), 25-38, HKL2.pdf
(3) Hyponormality of Toeplitz operators with polynomial symbols (with I.S. Hwang and I.H. Kim)
Math. Ann. 313(2) (1999), 247-261 HKL1.pdf
(2) Normal Toeplitz matrices (with D.R. Farenick, M. Krupnik and N. Krupnik)
SIAM J. Matrix Anal. Appl. 17(4) (1996), 1037-1043 FKKL.pdf
(1) Hyponormality and spectra of Toeplitz operators (with D.R. Farenick)
Trans. Amer. Math. Soc. 348(10) (1996), 4153-4174 FL1.pdf
(18) Hyponormality of Toeplitz operators in several variables by the weighted shifts approach (with C. Gu and I.S. Hwang)
Linear and Multilinear Algebras 68(8) (2020), 1695-1720, 19LMA.pdf
(17) An answer to a question of A. Lubin: The lifting problem for commuting subnormals (with S.H. Lee and J. Yoon)
Israel Journal of Mathmatics 222 (2017), 201-222, 15Lub.pdf
(16) Normal singular Cauchy integral operators with operator-valued symbols (with C. Gu, I.S. Hwang, D-O. Kang)
J. Math. Anal. Appl. 447(2017), 289-308, 17JMAA.pdf
(15) The mean transform of bounded linear operators (with S.H. Lee and J. Yoon)
J. Math. Anal. Appl. 410(2014), 70-81, 14JMAA.pdf
(14) Subnormality of Aluthge transforms of weighted shits (with S.H. Lee, J. Yoon)
Integral Equations Operator Theory 72 (2012), 241-251, 12IEOT.pdf
(13) Hyponormal operators with rank-two self-commutattors (with S.H. Lee)
J. Math. Anal. Appl. 351(2009), 616-626, 09JMAA.pdf
(12) Hyponormal Toeplitz operators with rational symbols (with I.S. Hwang)
J. Operator Theory 56(1)(2006), 47-58, 06JOT.pdf
(11) Quadratic hyponormality and 2-hyponormality for Toeplitz operators (with S.H. Lee)
Integral Equations Operator Theory 54(2006), 597-602, 06LL1.pdf
(10) k-hyponormality of finite perturbations of unilateral weighted shifts (with R.E. Curto)
Trans. Amer. Math. Soc. 357(12)(2005), 4719-4737 CuLe6.pdf
(9) On Aluthge transforms of p-hyponormal operators (with M. Cho and I.B. Jung)
Integral Equations Operator Theory (2005), ChoJL.pdf
(8) A new criterion for k-hyponormality via weak subnormality (with R.E. Curto and S.H. Lee)
Proc. Amer. Math. Soc. 133(6)(2005), 1805-1816, CLL2.pdf
(7) Solution of the quadratically hyponormal competion problem (with R.E. Curto)
Proc. Amer. Math. Soc. 131(8) (2003), 2479-2489, CuLe7.pdf
(6) On M-hyponormal weighted shifts (with J.S. Ham and S.H. Lee)
J. Math. Anal. Appl. 286 (2003), 116-124, HLL.pdf
(5) Subnormality and k-hyponormality of Toeplitz operators: A brief survey and open questions (with R.E. Curto)
Proc. Le Congres Int. des Math. de Rabat, (M. Mbekhta, ed.), The Theta Foundation, Bucharest, Romania, 73-81(2003) CuLe4.pdf
(4) Weak subnormality of operators (with R.E. Curto and I.S. Hwang)
Archiv Math. (Basel), 79(2002), no.5, 360-371, CuHL.pdf
(3) Subnormality and 2-hyponormality for Toeplitz operators (with R.E. Curto and S. H. Lee)
Integral Equations Operator Theory 44(2)(2002), 138-148, CLL.pdf
(2) Extensions and extremality of recursive weighted shifts (with R.E. Curto, Il Bong Jung)
Proc. Amer. Math. Soc. 130(2) (2002), 565-576, CJL.pdf
(1) Towards a model theory for 2-hyponormal operators (with R.E. Curto)
Integral Equation Operator Theory 44(3)(2002), 290-315, CuLe3.pdf
(18) Elementary properties of infinity-isometries on a Hilbert space (with M. Cho and C. Gu)
Linear Alg. & Appl. 511 (2016), 378-402, 16LAA.pdf
(17) Invariant subspaces for operators whose spectra are Caratheodory regions (with J. Kim)
J. Math. Anal. Appl. 371(2010), 184-189, 10-2JMAA.pdf
(16) The spectrum is continuous on the set of quasi-n-hyponormal operators (with I.H. Kim)
J. Math. Anal. Appl. 335(2007), 260-267, 07KL.pdf
(15) On a question of brown, Douglas, and Fillmore (with J. Kim)
J. Math. Anal. Appl. 336(2)(2007), 1486-1488, 07JL.pdf
(14) Spectral pictures of AB and BA (With R. Harte, Y.O. Kim)
Proc. Amer. Math. Soc. 134(1) (2006), 105-110, 06HKL.pdf
(13) On generalized Riesz points (with R.E.Harte and L.L.Littlejohn)
J. Operator Theory 42 (2002), 187-196, HaLL.pdf
(12) Weyl spectra and Weyl's theorem (with Y.M.Han)
Studia Math. 148(3) (2001), 193-206, HanL.pdf
(11) The boundedness below of 2x2 upper triangular operator matrices (with I.S. Hwang)
Integral Equations Operator Theory 39(3) (2001), 267-276, 01HL.pd
(10) The spectrum is continuous on the set of p-hyponormal operators (with I.S. Hwang)
Math. Z. 235 (2000), 151-157, HL1.pdf
(9) Invertible completions of 2x2 upper triangular operator matrices (with J.K. Han, H.Y. Lee)
Proc. Amer. Math. Soc. 128(1) (2000), 119-123, 00HLL.pdf
(8) Putnam's inequality of doubly commuting n-tuples for log-hyponormal operators (with M. Cho and B.P. Duggal)
Math. Proc. R. Ir. Acad. 100A(2) (2000), 163-169, CDL.dvi
(7) Riesz and Aiena operators (with R. Harte)
Rend. Circ. Mat. Palermo (2) 49(2) (2000), 391-394
(6) A folk theorem on Furuta inequality (with M. Cho, T. Furuta, J.I. Lee)
Sci. Math. 3(2) (2000), 229-231
(5) On the structure of polynomially compact operators (with Y.M. Han, S.H. Lee)
Math. Z. 232(2) (1999), 257-263 99HLL.pdf
(4) Weyl's theorem for operator matrices
Integral Equations Operator Theory 32(2) (1998), 319-331 98L1.pdf
(3) Another note on Weyl's theorem (with R.E.Harte)
Trans. Amer. Math. Soc. 349(5) (1997), 2115-2124, HaL1.pdf
(2) An index formula for chains (with R.E.Harte)
Studia Math. 116(3) (1995), 283-294, 95HLpdf
(1) The puncture neighbourhood theorem for incomplete spaces (with R.E.Harte)
J. Operator Theory 30 (1993), 217-226, 93HLpdf