APA (7th ed.) Citation

Ludwig-Walz, H., Siemens, W., Heinisch, S., Dannheim, I., Loss, J., & Bujard, M. (2023). Physical activity and physical fitness among children and adolescents after the onset of the COVID-19 pandemic in the WHO European Region: A systematic review protocol. BMJ open, 13(9), . https://doi.org/10.1136/bmjopen-2023-073397

Chicago Style (17th ed.) Citation

Ludwig-Walz, Helena, Waldemar Siemens, Sarah Heinisch, Indra Dannheim, Julika Loss, and Martin Bujard. "Physical Activity and Physical Fitness Among Children and Adolescents After the Onset of the COVID-19 Pandemic in the WHO European Region: A Systematic Review Protocol." BMJ Open 13, no. 9 (2023). https://doi.org/10.1136/bmjopen-2023-073397.

MLA (9th ed.) Citation

Ludwig-Walz, Helena, et al. "Physical Activity and Physical Fitness Among Children and Adolescents After the Onset of the COVID-19 Pandemic in the WHO European Region: A Systematic Review Protocol." BMJ Open, vol. 13, no. 9, 2023, https://doi.org/10.1136/bmjopen-2023-073397.