Bone sarcomas: ESMO-EURACAN-GENTURIS-ERN PaedCan Clinical Practice Guideline for diagnosis, treatment and follow-up - Strauss, S J; Frezza, A M; Abecassis, N; Bajpai, J; Bauer, S; Biagini, R; Bielack, S; Blay, J Y; Bolle, S; Bonvalot, S; Boukovinas, I; Bovee, J V M G; et al. (Annals of oncology, 2021)