Erratum: "Preliminary clinical experience with Calypso anchored beacons for tumor tracking in lung SBRT" [Med. Phys. (2020)]. Issue 1 (28th July 2020) - Sarkar, Vikren; Szegedi, Martin; Paxton, Adam; Nelson, Geoff; Rassiah‐Szegedi, Prema; Reddy, Chakravarthy B.; Tao, Randa; Hitchcock, Ying J.; Kokeny, Kristine E.; Salter, Bill J.