@article{McPherson1982,
author = {McPherson, J.M.},
title= {Hypernetwork sampling: Duality and differentiation among voluntary organizations},
year = {1982},
doi = {10.1016/0378-8733(82)90001-6},
journal = {Social Networks},
volume = {3},
number = {4},
pages = {225--249},
}