[[Z2 spin liquid]] obtained using [[slave-particle approach]] may be the first theoretical example of string-net liquid.<ref name="Read Sachdev pp. 1773–1776">{{cite journal | last=Read | first=N. Read| andlast2=Sachdev | first2=Subir Sachdev,| title=Large-N expansionNexpansion for frustrated quantum antiferromagnets,Phys.| Rev.journal=Physical Lett.Review 66Letters 1773| publisher=American Physical Society (1991APS) | volume=66 | issue=13 | date=1 March 1991 | issn=0031-9007 | doi=10.1103/physrevlett.66.1773 | pages=1773–1776}}</ref><ref>[[Xiao-Gang Wen]], Mean Field Theory of Spin Liquid States with Finite Energy Gaps and Topological Orders, [http://link.aps.org/doi/10.1103/PhysRevB.44.2664 Phys. Rev. B44, 2664 (1991)].</ref>
