“…For Cu, Mughrabi and Ungar [18] present data which support an internal stress about equal to ¼ the saturation stress. Work by Hecker and co-workers [19,20,21] and theoretical work by the same team [22] supports a value somewhat smaller, between 0.1 and 0.2. Lisiecki and Pedersen [23], on the basis of observations of wall configurations, suggest an average accommodation factor of about 1/3.…”