Panduga, V., Stocks, M. J., & Bosquillon, C. (2017). Ipratropium is ‘luminally recycled’ by an inter-play between apical uptake and efflux transporters in Calu-3 bronchial epithelial cell layers. International Journal of Pharmaceutics, 532(1), https://doi.org/10.1016/j.ijpharm.2017.08.112