Parnell, D., Pringle, A., McKenna, J., Zwolinsky, S., Rutherford, Z., Hargreaves, J., . . . Richardson, D. (2015). Reaching older people with PA delivered in football clubs: The reach, adoption and implementation characteristics of the Extra Time Programme. BMC Public Health.

Parnell, Daniel, Andy Pringle, Jim McKenna, Stephen Zwolinsky, Zoe Rutherford, Jackie Hargreaves, Lizzie Trotter, Michael Rigby, και David Richardson. "Reaching Older People With PA Delivered in Football Clubs: The Reach, Adoption and Implementation Characteristics of the Extra Time Programme." BMC Public Health 2015.

Parnell, Daniel, et al. "Reaching Older People With PA Delivered in Football Clubs: The Reach, Adoption and Implementation Characteristics of the Extra Time Programme." BMC Public Health 2015.