@article{Voigt1997,
	title = {Marshall-Peierls sign rule for excited states of the frustrated J1-J2
	Heisenberg antiferromagnet},
	author = {Andreas Voigt and Johannes Richter and Nedko B. Ivanov},
	day = {01},
	journal = {Physica A: Statistical and Theoretical Physics},
	month = {Nov},
	number = {3-4},
	pages = {269--275},
	url = {http://www.sciencedirect.com/science/article/B6TVG-3SPXB8W-10/1/4c9fbc14e290d0fb79efd4c576150413},
	volume = {245},
	year = {1997},
	biburl = {http://www.bibsonomy.org/bibtex/2b02b3a65f17b1ab65b6b0ab3e1cd0068/smicha},
	description = {Physica A},
	keywords = {Heisenberg antiferromagnet }
}