Lahti, P., X. Li, and Z. Wang. “Traces of Newtonian-Sobolev, Hajlasz-Sobolev, and BV Functions on Metric Spaces”. ANNALI SCUOLA NORMALE SUPERIORE - CLASSE DI SCIENZE, vol. 22, no. 3, Sept. 2021, pp. 1353-8, doi:10.2422/2036-2145.202001_003.