Cite

    Mónica Clapp and Bhakti Bhusan Manna. “Double- and single-layered sign-changing solutions to a singularly perturbed elliptic equation concentrating at a single sphere.” Communications in partial differential equations, vol. 42, no. 3, 2017, pp. 474–490. http://access.bl.uk/ark:/81055/vdc_100042870353.0x00004b