Park J, Yun KH.  Exotic smooth structures on $(2n+2l-1)\mathbb{CP}^2 \sharp (2n+4l-1)\overline{\mathbb{CP}}^2$.  Bull. Korean Math. Soc. 2010;47:961-971.  https://doi.org/10.4134/BKMS.2010.47.5.961