[1] Yotaro Takazawa. "Approximation algorithm for the stochastic prize-collecting set multicover problem." Operations Research Letters 50.2 (2022): 224-228.
[2] Yotaro Takazawa, Shinji Mizuno, and Tomonari Kitahara. "An approximation algorithm for the partial covering 0–1 integer program." Discrete applied mathematics 275 (2020): 126-133.
[3] Yotaro Takazawa, and Shinji Mizuno. "A 2-approximation algorithm for the minimum knapsack problem with a forcing graph." Journal of the Operations Research Society of Japan 60.1 (2017): 15-23.