Talks and Publications

   Talks: 

1.  On the spanning tree with bounded degree sum of two adjacent vertices, KAIST-VIASM Annual Meeting on Mathematical Sciences, KAIST, October, 2025.

2. Unicity theorems for the Gauss maps of complete minimal surfaces, Workshop on Harmonic Analysis and Several Complex Variables, Viasm, November, 2023.

3. Estimates for the Gaussian curvature of Riemann surfaces and related problems, Workshop on Some selected problems in Complex Analysis and Complex Geometry, Viasm, December, 2021. 

4. Value distribution theory of the Gauss map of a complete minimal surface on annular ends, National Conference on Algebra-Number Theory- Geometry -Topology, Thai Nguyen, October, 2021. 

5. Spanning trees with at most 4 leaves in K_{1,5}-free graphs, Second Vietnam workshop on Graph theory and Discrete Geometry, VIASM, Hanoi, January 2019.

6.  A new progress on weak Dirac conjecture, First Vietnam workshop on Graph theory and Discrete Geometry, VIASM, Hanoi, September 2016.

7.  A new progress on Dirac conjecture and its relations, Aspect of Analysis and Geometry, Hanoi, May 2016.

8.  An estimate for the Gaussian curvature of minimal surfaces in Rm whose Gauss map is ramified over a set of hyperplanes, National Conference on Algebra, Geometry and Topology, Tuanchau, Halong, QuangNinh province, December 2014.

9. Uniqueness problems with truncated Multiplicities of Meromorphic mappings, Vietnamese National Conference in Mathematics, Quy Nhon, August 2008.

10. Unicity problem with truncated Multiplicities of Meromorphic mappings in several complex variables, “International Conference on Number Theory and Related Topics”, Vietnam Institute of Mathematics, December 2006.

    Publications and accepted papers:

1.  Spectral radius conditions for a connected graph to have a spanning tree whose stem has few leaves, accepted for publication in Acta Mathematica Hungarica.

2. (with Nguyen Gia Hien) Spanning trees of claw-free graphs with few leaves and branch vertices, Discrete Mathematics & Theoretical Computer Science, November 20, 2025, vol. 27:3 - https://doi.org/10.46298/dmtcs.15247 

3. (with Pham Ngoc Diep and Bui Ngoc Tu) Spanning trees of a $K_{1,5}$-free graph with at most seven leaves and branch vertices in total, Studia Sci. Math. Hungar. 62 (4) (2025), 305-319.   https://doi.org/10.1556/012.2025.04334 

4. Spanning trees of $K_{1,4}$-free graphs with a bounded number of leaves and branch vertices, Acta Math. Vietnam 50, 263–271 (2025).  https://doi.org/10.1007/s40306-025-00568-6 

5. (with Nguyen Hoang Trang) Spanning trees with at most $5$ leaves and branch vertices in total of $K_{1,5}$-free graphs, Taiwanese J. Math., 28 (5) 847 - 855, October, 2024.  DOI: 10.11650/tjm/240606 

6. (with Le Dinh Nam and Ngoc Diep Pham) Spanning trees of $K_{1,4}$-free graphs whose reducible stems have few leaves, Period. Math. Hung. 3 (2024), 61-71. https://doi.org/10.1007/s10998-024-00572-7 

7. (with Duy Trung Doan, Thi Thanh Chau Do, Ngoc Diep Pham and Ingo Schiermeyer) The conflict-free connection number and the degree-sum of graphs, Applied Mathematics and Computation 482 (2024) 128981.

8. (with Dang Dinh Hanh, Le Dinh Nam and Nguyen Huu Nhan), Spanning trees whose stems are Caterpillars, Studia Sci. Math. Hungar. 61(2) (2024), 134-146. https://doi.org/10.1556/012.2024.04310 

9. Progress on sufficient conditions for a graph to have a spanning k-ended tree, Vietnam J. Math. Volume 52 (2024), 69-74. https://doi.org/10.1007/s10013-022-00553-8 .

10. Spanning trees of a claw-free graph whose reducible Stems have few leaves, Studia Sci. Math. Hungar. 60 (2023), no. 1, 2-15. https://doi.org/10.1556/012.2023.01538.

11. (with Doan Duy Trung and Ingo Schiermeyer) The conflict-free vertex-connection number and minimum degree, Graphs and Combinatorics 38, 157 (2022).  

12. A note on independence number, connectivity and k-ended tree, Discrete Applied Mathematics 305 (2021), 142–144.  https://doi.org/10.1016/j.dam.2021.09.004 

13. (with Dang Dinh Hanh ,Nguyen Thanh Loan and Ngoc Diep Pham) Spanning trees whose reducible stems have a few branch vertices, Czech Math J , 71, No. 3, pp. 697-708, 2021.

14. (with Dang Dinh Hanh and Nguyen Thanh Loan), Spanning trees with few peripheral branch vertices, Taiwanese Journal of Mathematics, Vol. 25, No. 3, pp. 435- 447, June 2021, DOI: 10.11650/tjm/201201.

15. (with Nguyen Hoang Trang), Modified defect relations of the Gauss maps of complete minimal surfaces on annular ends, Publicationes Mathematicae Debrecen  97/ 3-4 (2020), 265-287. 

16. (with Dang Dinh Hanh), Spanning trees of connected $K_{1, t}-$free graphs whose stems have a few leaves, Bulletin of the Malaysian Mathematical Sciences Society 43 (2020), 2373-2383. DOI:  https://link.springer.com/article/10.1007/s40840-019-00812-x

17. Gaussian curvature and unicity problem of Gauss maps of various classes of surfaces,  Nagoya Mathematical Journal 240 (2020), 275-297 . DOI: https://doi.org/10.1017/nmj.2019.5

18. (with Yuan Chen and Dang Dinh Hanh),  Spanning trees with at most 4 leaves in $K_{1,5}-$free graphs, Discrete Mathematics 342 (2019) 2342–2349.

19. (with Si Duc Quang)  Unicity theorems with truncated multiplicities of meromorphic mappings in several complex variables for few fixed targets, Ukrainian  Mathematical Journal, Ukr. Mat. Zh. - 71, No 3(2019). 412-432. 

20.  Non-integrated defect relations for the Gauss map of a complete minimal surface with finite total curvature in R^m,  Bull. Math. Soc. Sci. Math. Roumanie,  Tome 61 (109) No. 2, (2018), 187-199. 

21. (with Yu Kawakami), A note on a unicity theorem for the Gauss maps of complete minimal surfaces in Euclidean four-space,  Canad. Math. Bull. Vol. 61 (2) (2018 ), 292–300 . 

22. Modified defect relations of the Gauss map and the total curvature of a complete minimal surface, Topology and its Applications, 234 (2018), 178-197. 

23. (with Le Bich Phuong and Pham Duc Thoan), The ramification of the Gauss map and the total curvature of complete minimal surfaces, Topology and its Applications, 199 (2016), 32-48. 

24. (with Gerd Dethloff and Pham Duc Thoan), Ramification of the Gauss map of complete minimal surfaces in Rm on annular ends,  Colloq. Math. 142 (2016), 149-167. 

25. (with Nguyen Van Trao), Non-integrated defect relations for the Gauss map of complete minimal surfaces with finite total curvature, J. Math. Anal. Appl. 430 (2015) 76–84.

26. (with Gerd Dethloff),  Ramification of the Gauss map of complete minimal surfaces in R3 and R4 on annular ends, Ann. Fac. Sci. Toulouse Math., 23(2014), no. 4, 829-846.

27. An estimate for the Gaussian curvature of minimal surfaces in Rm whose Gauss map is ramified over a set of hyperplanes, Differential Geom. Appl. 32 (2014), 130--138. 

28. A unicity theorem with truncated counting function for meromorphic mappings. Acta Math. Vietnam. 35 (2010), no. 3, 439—456. 

29. (with Si Duc Quang and Do Duc Thai) Unicity theorems with truncated multiplicities of meromorphic mappings in several complex variables sharing small identical sets for moving targets. Internat. J. Math. 21 (2010), no. 9, 1095--1120.

Preprints:

1.  (with Gerd  Dethloff and Do Duc Thai) Unicity theorems for the Gauss maps of complete minimal surfaces, submitted.

2. (with Ngoc Diep Pham) A note on degree sum for a planar graph having a hamiltionian path, submitted. 

3. Spanning tree with bounded degree sum of two adjacent vertices and (1,2)-rainbow connection, submitted.

4. (with Le Dinh Nam, Truong Ngoc Van Chinh and Vu Minh Duc) Degree conditions for rainbow and properly colored spanning trees in edge-colored graphs, submitted.

5. (with Dang Dinh Hanh and Vu Quang Minh) The number of cut-edges  and conflict-free connection number in planar graphs, submitted.

6. (with Dinh Hanh Dang, Trung Duy Doan and Vu Quang Minh) Degree sum conditions for a graph to have bounded conflict-free connection number, submitted.

Unpublished papers:

1. (with Tien Cuong Phi), A new progress on Weak Dirac conjecture, https://arxiv.org/abs/1607.08398

2. (with Dang Dinh Hanh), Spanning trees with at most 2 branch vertices in claw - free graphs,  arXiv:1806.00734 .