E. M. Arkin and R. Hassin, Approximation algorithms for the geometric covering salesman problem, Discrete Applied Mathematics, vol.55, issue.3, pp.197-218, 1994.
DOI : 10.1016/0166-218X(94)90008-6

D. Bhadauria and V. Isler, Data gathering tours for mobile robots, 2009 IEEE/RSJ International Conference on Intelligent Robots and Systems, 2009.
DOI : 10.1109/IROS.2009.5354343

G. D. Celik and E. Modiano, Random access wireless networks with controlled mobility, 2009 8th IFIP Annual Mediterranean Ad Hoc Networking Workshop, 2009.
DOI : 10.1109/MEDHOCNET.2009.5205194

M. D. Berg, J. Gudmundsson, M. J. Katz, C. Levcopoulos, M. H. Overmars et al., TSP with neighborhoods of varying size, Journal of Algorithms, vol.57, issue.1, pp.22-36, 2005.
DOI : 10.1016/j.jalgor.2005.01.010

A. Dumitrescu and J. S. Mitchell, Approximation algorithms for TSP with neighborhoods in the plane, Journal of Algorithms, vol.48, issue.1, pp.135-159, 2003.
DOI : 10.1016/S0196-6774(03)00047-6

K. Elbassioni, A. V. Fishkin, and R. Sitters, APPROXIMATION ALGORITHMS FOR THE EUCLIDEAN TRAVELING SALESMAN PROBLEM WITH DISCRETE AND CONTINUOUS NEIGHBORHOODS, International Journal of Computational Geometry & Applications, vol.19, issue.02
DOI : 10.1142/S0218195909002897

K. Elbassioni, A. V. Fishkin, and R. Sitters, On Approximating the TSP with Intersecting Neighborhoods, ISAAC, 2006.
DOI : 10.1007/11940128_23

A. Ephremides, Energy concerns in wireless networks, IEEE Wireless Communications, vol.9, issue.4, pp.48-59, 2002.
DOI : 10.1109/MWC.2002.1028877

S. R. Gandham, M. Dawande, R. Prakash, and S. Venkatesan, Energy efficient schemes for wireless sensor networks with multiple mobile base stations, GLOBECOM '03. IEEE Global Telecommunications Conference (IEEE Cat. No.03CH37489), 2003.
DOI : 10.1109/GLOCOM.2003.1258265

D. Goldenberg, J. Lin, A. S. Morse, B. Rosen, and Y. R. Yang, Towards mobility as a network control primitive, Proceedings of the 5th ACM international symposium on Mobile ad hoc networking and computing , MobiHoc '04, 2004.
DOI : 10.1145/989459.989481

J. Gudmundsson and C. Levcopoulos, A fast approximation algorithm for TSP with neighborhoods, Nordic Journal of Computing, vol.6, issue.4, pp.469-488, 1999.

C. Intanagonwiwat, R. Govindan, D. Estrin, J. Heidemann, and F. Silva, Directed diffusion for wireless sensor networking, IEEE/ACM Transactions on Networking, vol.11, issue.1, pp.2-16, 2003.
DOI : 10.1109/TNET.2002.808417

S. Jain, R. Shah, W. Brunette, G. Borriello, and S. Roy, Exploiting Mobility for Energy Efficient Data Collection in Wireless Sensor Networks, Mobile Networks and Applications, vol.11, issue.3, pp.327-339, 2006.
DOI : 10.1007/s11036-006-5186-9

D. Jea, A. A. Somasundara, and M. B. Srivastava, Multiple Controlled Mobile Elements (Data Mules) for Data Collection in Sensor Networks, DCOSS, 2005.
DOI : 10.1007/11502593_20

R. C. Larson and A. R. Odoni, Urban Operations Research, 1981.

H. Levy, M. Sidi, and O. L. Boxma, Dominance relations in polling systems, Queueing Systems, vol.4, issue.3, pp.155-172, 1990.
DOI : 10.1007/BF02411471

J. Luo and J. P. Hubaux, Joint mobility and routing for lifetime elongation in wireless sensor networks, Proc. IEEE INFOCOM, 2005.

C. S. Mata and J. S. Mitchell, Approximation algorithms for geometric tour and network design problems (extended abstract), Proceedings of the eleventh annual symposium on Computational geometry , SCG '95, pp.360-369, 1995.
DOI : 10.1145/220279.220318

M. Perillo, Z. Cheng, and W. Heinzelman, An analysis of strategies for mitigating the sensor network hot spot problem, The Second Annual International Conference on Mobile and Ubiquitous Systems: Networking and Services, 2005.
DOI : 10.1109/MOBIQUITOUS.2005.10

R. Shah, S. Roy, S. Jain, and W. Brunette, Data MULEs: Modeling a three-tier architecture for sparse sensor networks, IEEE SNPA, 2003.

Y. Shi and Y. T. Hou, Theoretical Results on Base Station Movement Problem for Sensor Network, IEEE INFOCOM 2008, The 27th Conference on Computer Communications, 2008.
DOI : 10.1109/INFOCOM.2008.9

A. A. Somasundara, A. Ramamoorthy, and M. B. Srivastava, Mobile Element Scheduling for Efficient Data Collection in Wireless Sensor Networks with Dynamic Deadlines, 25th IEEE International Real-Time Systems Symposium, 2004.
DOI : 10.1109/REAL.2004.31

A. A. Somasundara, A. Kansal, D. Jea, D. Estrin, and M. B. Srivastava, Controllably mobile infrastructure for low energy embedded networks, IEEE Transactions on Mobile Computing, vol.5, issue.8, pp.958-973, 2006.
DOI : 10.1109/TMC.2006.109

J. M. Steele, Probabilistic and Worst Case Analyses of Classical Problems of Combinatorial Optimization in Euclidean Space, Mathematics of Operations Research, vol.15, issue.4, p.749, 1990.
DOI : 10.1287/moor.15.4.749

R. Sugihara and R. Gupta, Optimizing Energy-Latency Trade-Off in Sensor Networks with Controlled Mobility, IEEE INFOCOM 2009, The 28th Conference on Computer Communications
DOI : 10.1109/INFCOM.2009.5062188

H. Takagi, Queueing analysis of polling models: an update, Stoch. Analy. of Computer and Commun. Sys, pp.267-318, 1990.

M. M. Tariq, M. Ammar, and E. Zegura, Message ferry route design for sparse ad hoc networks with mobile nodes, Proc. ACM MobiHoc, 2006.

W. Wang, V. Srinivasan, and K. Chua, Using mobile relays to prolong the lifetime of wireless sensor networks, Proceedings of the 11th annual international conference on Mobile computing and networking , MobiCom '05, 2005.
DOI : 10.1145/1080829.1080858

Y. Xie and K. C. Chang, Stability-constrained optimization for energy efficiency in polling-based wireless networks, Proceedings of the 1st international conference on Performance evaluation methodolgies and tools , valuetools '06, 2006.
DOI : 10.1145/1190095.1190124