1. Ling Chen, Twisted Hamiltonian Lie algebras and their multiplicity-free representations, Acta Mathematica Sinica, English Series 27(1) (2011), 45-72.
2. Ling Chen, Multiplicity-one representations of divergence-free Lie algebras, Journal of Algebra 352 (2012), 1-61.
3. Ling Chen, Generalized multiplicity-free representations of nongraded divergence-free Lie algebras, Journal of Lie Theory 23(2) (2013), 507-549. 
4. Ling Chen, On axiomatic approaches to intertwining operator algebras, to appear in Communications in Contemporary Mathematics, 2015.
5. Ling Chen, An S3-symmetry of the Jacobi identity for intertwining operator algebras, New York Journal of Mathematics 21(2015), 657-698.