Erratum for “Wall Shear Stress in the Early Stage of Unsteady Turbulent Pipe Flow” by S. He and C. Ariyaratne

The authors regret that the values of the vertical axis of Fig. 2 of the original paper are incorrect. They should be doubled. This is because diameter values were used in places in which radius values should have been used for calculating the unsteady friction factor $f_{u0}$ in Eq. (14). The correct figure with $f_{u0}$ as defined by Eq. (14) appears in this erratum.