Liu, Jun, 1986-. "Safety performance of rural four-lane undivided roadways and rural four-lane roadways with a two-way left-turn lane." University of Georgia. Map and Government Information Library. 2020-07, https://dlg.galileo.usg.edu/do:dlg_ggpd_s-ga-bt700-pr4-bm1-b2020-bs24-belec-p-btext.

Liu, Jun, 1986- (2020-07). Safety performance of rural four-lane undivided roadways and rural four-lane roadways with a two-way left-turn lane. Retrieved from https://dlg.galileo.usg.edu/do:dlg_ggpd_s-ga-bt700-pr4-bm1-b2020-bs24-belec-p-btext

Liu, Jun, 1986-. "Safety performance of rural four-lane undivided roadways and rural four-lane roadways with a two-way left-turn lane." 2020-07. November 3, 2026. https://dlg.galileo.usg.edu/do:dlg_ggpd_s-ga-bt700-pr4-bm1-b2020-bs24-belec-p-btext.