Zhu, M., He, H., Fan, M., Ma, H., Ren, H., Zeng, J., & Gao, H. (2018). Application and optimization of solid-state fermentation process for enhancing polygalacturonase production by Penicillium expansum. International Journal of Agricultural and Biological Engineering, 11(6), 187–194. https://doi.org/10.25165/ijabe.v11i6.3673