Paulsen, A. et al. 2007. Effect of hydroxyapatite coating on risk of revision after primary total hip arthroplasty in younger patients: Findings from the Danish Hip Arthroplasty Registry. Acta Orthopaedica. 78, 5 (Jan. 2007), 622–628. DOI:https://doi.org/10.1080/17453670710014310.