Fang, Fuquan Max Planck Institute for Mathematics, Max Planck Society;
https://doi.org/10.1515/form.2004.022 (Publisher version)
Fang, F., & Pan, J. (2004). Secondary Brown-Kervaire quadratic forms and pi-manifolds. Forum Mathematicum, 16(4), 459-481. doi:10.1515/form.2004.022.