Ohio Wine Producers Association. (1997). Portage Hills Vineyards, 1997. https://oaks.kent.edu/node/5978
Ohio Wine Producers Association. 1997. “Portage Hills Vineyards, 1997”. https://oaks.kent.edu/node/5978.
Ohio Wine Producers Association. Portage Hills Vineyards, 1997. 1 May 1997, https://oaks.kent.edu/node/5978.