1. H.H. Klepfer. GEAP-4089 (1962).
2. R.N. Duncan, A.S. Mehner and H.H. Klepfer. GEAP-5649 (1968).
3. H.H. Klepfer. U.S. patent No. 3287111 (1965).
4. E. Tolksdorf. Danish Atomic Energy Commission, Risø. Private communication.
5. Massive grain growth during aging of quenched Zr/1.25 wt% Cr/0.1 wt% Fe