Widiyanto, W. (2024) “Article RETRACTED due to manipulation by the authors Los diferentes resultados en lsa habilidades de servicio de los tenistas jóvenes evaluadas según el género y la edad (The Differences Result in Serve Skill of Junior Tennis Players Assessed Based on Gender and Age): Article RETRACTED due to manipulation by the authors”, Retos, 54, pp. 272–278. doi:10.47197/retos.v54.102757.