@inproceedings{henrik1994self-duality,
title={Self-duality and differentiable structures on the connected sum of complex projective planes},
author={Henrik Pedersen, and Yat Sun Poon},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20191020220515357042325},
booktitle={Proceedings of the American Mathematical Society},
volume={121},
number={3},
pages={859-864},
year={1994},
}

Henrik Pedersen, and Yat Sun Poon. Self-duality and differentiable structures on the connected sum of complex projective planes. 1994. Vol. 121. In Proceedings of the American Mathematical Society. pp.859-864. http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20191020220515357042325.