Lectures ( in Seminars/Symposia/Conferences) Delivered:

(One-hour)Invited Lecture, Applied Mathematics Section, Institute of Technology, Banaras Hindu University, (Nov. 2, 1985).

    (One-hour ) Invited Lecture,Indian Society for Technical Education - Winter School on Mathematical Models of Flow Phenomena in Porous Media held at the Inst. of Tech., B.H.U. (Dec. 8-22, 1986).

(One-hour) Invited Lecture, Department of Mathematics, Gorakhpur University, (Nov. 20, 1987).

(One-hour) Invited Lecture, Department of Mathematics, I.I.T. Bombay (Jan. 8, 1988).

(Half-hour) Invited Lecture, Indian Science Congress, Mathematics Section, Madurai University (Jan.10, 1989).

(Series of Invited Lectures) Department of Mathematics and Statistics, Bundelkhand University, (July, 1989).

(2 of One-hour each) Invited Lectures, Academic Staff College, Banaras Hindu University, Refresher Course in Mathematics on Analysis and Mathematical Methods for University and College Lecturers (Sept. 11 - 13, 1991).

(Half-hour) Invited Lecture, Indian Mathematical Society - Symposium on "Recent advances in Nonlinear Analysis", held at the Institute of Technology, B.H.U., Varanasi (March 23, 1993).

(Series of Invited Lectures) Department of Mathematics and statistics, R.D.University, Jabalpur (Nov. 1994).

(2 of One-hour each) Guest Lectures, Winter School in the Chemical Applications of Statistical Mechanics, Department of Chemistry and the RSIC, I.I.T. Bombay (Dec.10, 1994).

(One-hour) Guest Lecture, Workshop in Mathematics, Department of Mathematics, IIT Bombay (Nov. 1995).

(One-hour) Invited Lecture, Department of Mathematics, Central University of Hyderabad, (Sept.1996)

(One-hour) Invited Lecture, Academic Staff College, Department of Mathematics, Bombay University (Oct.-Nov. 1996)

(One-hour) Invited Lecture, Department of Mathematics, I.I.Sc. Bangalore ( July 31, 1997)

(One-hour) Invited Lecture, Seventh Annual Conference of Vijnana Parishad of India, Harcourt Butler Technological Institute,Kanpur (Oct.25, 1997)

(One-hour) Invited Lecture, Department of Mathematics, IIT Bombay (April 7, 1998)

(One-hour) Invited Lecture, International Conference on Scientific Computing and modeling, S.N. Bose Centre for Basic Sciences, Calcutta (July 10, 1998).

(One-hour) Invited Lecture, International Conference of the Academy of Physical Sciences held at the University of Allahabad (December 1999).

(One-hour) Invited Lecture, Joint 9^th National Conference of Vijnana Parishad of India on Applied and Industrial Mathematics and 5^th Annual Conference of Indian Society of Information Theory and Applications held at NSIT, New Delhi (February 2002).

(One-hour) Invited Lecture, National Seminar on Recent Advances in Fluid Mechanics held at Gulbarga University, Karnatak (September 12, 2002).

(One-hour) Popular Lecture, Mathematics Association of I.I.T. Bombay and Bombay Mathematical Colloquium (under the Popular Lecture Series in Mathematics) held at the Department of Mathematics, IIT Bombay (October 25, 2002).

(One-hour) Invited Lecture, National Seminar on Current Trends in Mathematics held at the University of Allahabad (Nov.10, 2002).

(One-hour) Invited Lecture, Department of Mathematics, Banaras Hindu Uni-versity (June 13, 2003)

(One-hour) Invited Lecture, International Conference on Non-linear wave phenol-menon, IISc Bangalore (January 5, 2004).

(One Hour) Key Note Address, National Conference on Information Technology, Operations Research and Computing held at Dr. B.R. Ambedkar University, Agra (10^th April 2004).

(One Hour) Invited Lecture, delivered at the Department of Mathematics, Univesity of Southern California (June 25, 2004).

(40 Minutes) Invited Lecture, Fourth World Congress of Nonlinear Analysts 2004, organized by the Florida Institute of Technology, held at Orlando, Florida (July 3, 2004)

(One Hour) Inaugural Address, Workshop on Optical Communication, organized by the Department of Electronics and Telecommunication Engineering, VES Institute of Technology, Mumbai (August 8, 2004).

(One-hour) Invited Lecture, International Conference on Mathematical Fluid Dynamics held at the Department of Mathematics and Statistics, University of Hyderabad, Hyderabad (December 3, 2004).

(Half-Hour) Invited Lecutre, delivered at a research conference on New Perspectives for Boundary Value Problems and their asymptotics held at the University of Texas-Pan American, USA (May 17, 2005).

(One-Hour) Invited Lecutre, delivered to the Applied Mathematics and Physics Unit of ISI Kolkata (April, 2006).

(One-Hour) Invited Lecutre, delivered at Bhaskracharya Pratisthana, Pune University (Nov, 2006).

(One-Hour) Invited Lecutre, delivered at Indian Science Congress, held at Annamalai University (Jan. 2007).

(Half-Hour) Invited Lecutre, delivered at the American Mathematical Society (AMS) meeting held at DePaul University, Chicago, USA (Oct, 2007).

(Half-Hour) Invited Lecture, delivered at the AMS meeting held at the University of Albuquerque, New Maxico, USA (Oct, 2007).

(One-Hour) Invited Lecutre, delivered at the Department of Mathematics, Stanford University, USA (Jan, 2008).

(One-Hour) Invited Lecutre, delivered to the faculty and PG students under the Distinguished Colloquium Sereis at North Maharashtra University (March, 2008).

(One-Hour) Invited Lecutre, delivered the National Seminar on Analysis, Differential Equations and Applications, held at M.S. University, Baroda (Jan, 2009).

(One-Hour) Invited Lecutre, delivered at the Seminar meeting of Hyperbolic Systems of PDEs held at IIT Bombay from 20-23 Nov. 2009.

(One-Hour) Invited Lecutre, delivered at the Indian Society of Theoretical and Applied Mechanics (ISTAM-2009) held at NSIT, New Delhi from 18-21 Dec. 2009, and chaired a Technical Session on Mechanics of Fluids.