1. Metallic copper as an intra-uterine adjunct to the "T" device;Zipper;Am J Obstet Gynecol,1969
2. Intrauterine contraception using the copper 7 device;Newton;Lancet,1972
3. Comparative experience with newer models of the copper T in the USA;Tatum,1974
4. Copper IUCDs and the pregnancy rate;Snowden;Br J Fam Planning,1981
5. Intrauterine devices. Population reports series B,1988