Simonsen, Anne Birgitte, et al. “A Challenging Case of Subcutaneous and Mucosal Haemorrhage Caused by Urticarial Vasculitis (Urticaria Haemorrhagica Profunda)”. Acta Dermato-Venereologica, vol. 100, no. 4, Feb. 2020, pp. 1-2, doi:10.2340/00015555-3410.