R. Seifi, Stress intensity factors for internal surface cracks in autofrettaged functionally graded thick cylinders using weight function method, Theor. Appl. Fract. Mech., 75 (2015) 113-123.
 I. Eshraghi, N. Soltani, Stress intensity factor calculation for internal circumferential cracks functionally graded cylinders using the weight
function approach, Eng. Fract. Mech., 134 (2015) 1-19.
 A. Shaghaghi-Moghaddam, M. Alfano, M. Ghajar, Determining the mixed mode stress intensity factors of surface cracks in functionally graded hollow cylinders, Mater. Des., 43 (2013) 475-484.
 A.M. Afsar, M. Anisuzzaman, Stress intensity factors of two diametrically opposed edge cracks in a thick-walled functionally graded material cylinder, Eng. Fract. Mech., 74 (2007) 1617-1636.
 Y. Ootao, R. Kawamura, Y. Tanigawa, R. Imamura, Optimization of material composition of nonhomogeneous hollow sphere for thermal stress relaxation making use of neural network, Comput. Meth. Appl. Mech. Eng., 180 (1999) 185-201.
 Y. Ootao, R. Kawamura, Y. Tanigawa, R. Imamura, Optimization of material composition of nonhomogeneous hollow circular cylinder for thermal stress relaxation making use of neural network, J. Thermal. Stress., 22 (1999) 1-22.
 A.R. Saidi, S.R. Atashipour, E. Jomehzadeh, Exact elasticity solutions for thick- walled FG spherical pressure vessels with linearly and exponentially varying properties, Int. J. Eng., Transactions A: Basics, 22(4) (2009) 405-416.
 M.H. Heydari, N. Choupani, A new comparative method to evaluate the fracture properties of laminated composite, Int. J. Eng., Transactions C: Aspects, 27(6) 991-1004.
 A.R. EL-Desouky, M.S. EL-Wazery, Mixed mode crack propagation of zirconia/nickel functionally graded materials, Int. J. Eng.,Transactions B:
Application, 26(8) (2013) 885-894.
 C.H. Zhang, M. Cui, J.Wang, X.W. Gao, J. Sladek, V. Sladek, 3D crack analysis in functionally graded materials, Eng. Fract. Mech., 78 (2011) 585-604.
 J.L. Wearing, S.Y. Ahmadi-Brooghani, the evaluation of stress intensity factors in plate bending problems using the dual boundary element method, Eng. Anal. Bound. Element., 23 (1999) 3-19.
 J.P. Pereira, C.A. Duarte, Extraction of stress intensity factors from generalized finite element solutions, Engin. Anal. Bound. Element., 29 (2005) 397-413.
 J. Purbolaksono, A.A. Ali, A. Khinani, A.Z. Rashid, Evaluation of stress intensity factors for multiple surface cracks in bi-material tubes, Eng. Anal. Bound. Element., 33(11) (2009) 1339-1343.
 A. Barroso, E. Graciani, V. Mantic, F. Paris, A least squares procedure for the evaluation of multiple generalized stress intensity factors at 2D multimaterial corners by BEM, Eng. Anal. Bound. Element., 36 (2012) 458-470.
 I.A. Alatawi, J. Trevelyan, A direct evaluation of stress intensity factors using the Extended Dual Boundary Element Method, Eng. Anal. Bound. Element., 52 (2015) 56-63.
 N. Tutuncu, M. Ozturk, Exact Solution for stresses in functionally graded pressure vessels, Composites, part B, 32 (2001) 683-686.
 C.O. Horgan, A.M. Chan, The pressurized hollow cylinder or disk problem for functionally graded isotropic linearly elasticity, J. Elast., 55 (1999) 43-59.
 M. Jabbari, S. Sohrabpour, M.R. Eslami, Mechanical and thermal stresses in a functionally graded hollow cylinder due to radially symmetric loads, Int. J. Pres. Ves. Pip., 79 (2002) 493-497.
 A. Ghasemi, A. Kazemian, M. Moradi, Analytical and numerical investigation of FGM pressure vessel reinforced by laminated composite materials, J. Sol. Mech., 6(1) (2014) 43-53.
 Y. Chen, X. Lin, Elastic analysis for thick cylinders and spherical pressure vessels made of functionally graded materials, Comput. Mater. Sci., 44(2) (2008) 581-587.
 K. Abrinia H. Naee, F. Sadeghi, F. Djavanroodi, New analysis for the FGM thick cylinders under combined pressure and temperature loading, American J. Appl. Sci., 5(7) (2008) 852-859.
 M.H. Aliabad, The Boundary Element Method: Applications in solids and structures, 2, John Wiley & Sons, (2002).
 X.W. Gao, T.G. Davies, Boundary Element Programming in Mechanics, Cambridge University Press, (2002).
 C.A. Brebbia, J. Dominguez, Boundary Elements an Introductory Course, McGraw Hill, New York, NY, (1989).
 X.W. Gao, The radial integration method for evaluation of domain integrals with boundary-only discretization, Eng. Anal. Bound. Element., 26 (2002) 905-916.
 X.W. Gao, A boundary element method without internal cells for two-dimensional and three dimensional elastoplastic problems, J. Appl. Mech., 69 (2002) 154-60.
 J.W. Eischen, Fracture of nonhomogeneous materials, Int. J. Fract., 34 (1987) 3-22.
 C. Guozhong, Z. Kangda, W.U. Dongdi, Stress intensity factors for internal semi- elliptical surface cracks in pressurized thick-walled cylinders using the hybrid boundary element method, Eng. Fract. Mech., 52 (1995) 1055-1064.
 M.J. McNary, Implementation of the extended finite element method (XFEM) in the ABAQUS software package, MSc. Thesis in mechanical engineering, Georgia Institute of Technology, (2009).