@article {9572,
	title = {Soft modes in order-disorder ferroelectrics},
	journal = {Applied Physics Letters},
	year = {2001},
	pages = {1333-1335},
	doi = {10.1063/1.1392971},
	author = {Zhi-Rong Liu and Wenhui Duan and Bing-Lin Gu and Xiao-Wen Zhang}
}
