1. (Daniels and Härdtl, 1976; Daniels, 1976; Daniels and Wernicke, 1976; Hennings, 1976; Wernicke, 1976; Eror and Smyth, 1978; Chan et al, 1982; Smyth, 1985; Raymond and Smyth, 1993, 1994; Smyth, 1994; Denk et al., 1995; Maier, 1996)
2. Scott and Araujo (1989); Scott et al. (1989); Duiker et al. (1990); Pan et al. (1992b); Yoo and Desu (1992c); Desu and Yoo (1993a); Brennan (1993); Furuta and Uchino (1993); Desu and Yoo (1993b); Scott et al. (1993); Minara et al. (1994b, a); Chen et al. (1994b); Warren et al. (1995b, d); Pawlaczyk et al. (1995); Pan et al. (1996); Gruverman et al. (1996a); Hill et al. (1996); Colla et al. (1997); Warren et al. (1997c); Colla et al. (1998b, c, a); Du and Chen (1998a); Brazier et al. (1999); Weitzing et al. (1999); Kim et al. (1999b); Bobnar et al. (1999); Tagantsev and Stolichnov (1999); Nuffer et al. (2000) and many others.
3. RuOx, Bernstein et al. (1993); Vijay and Desu (1993); Bursill et al. (1994); Lee et al. (1995b); Desu (1995); Taylor et al. (1995); Kim et al. (1999a); Lao.5Sr0.5CoO3, Ramesh and Keramidas (1995); Al-Shareef et al. (1996b); Cillesen et al. (1997); Han and Lee (2000); Cheng et al. (2000); YBa2Cu3O7 Ramesh et al. (1992); Lee et al. (1993); Koo et al. (1999); IrOx, Hase et al. (1998); Yi et al. (2001); BaRuO3, Koo et al. (1999); LaNiO3, Kim et al. (2000a); Wang et al. (2001); Chao and Wu (2001); Meng et al. (2001); Kim and Lee (2002); SrRuO3, Tsukada et al. (2000)
4. RAINBOW actuators are disc shaped actuators, mostly of PZT, which were chemically reduced on one side to significantly change the piezoelectric effect across the thickness. The strain is obtained along the thickness direction of the plate due to the warping of the plate (Haertling, 1994).