@article{doi:10.1302/0301-620X.63B1.7204473,
author = {Apley, AG and Wientroub, S},
title = {The sagging rope sign in Perthes' disease and allied disorders},
journal = {The Journal of Bone & Joint Surgery British Volume},
volume = {63-B},
number = {1},
pages = {43-47},
year = {1981},
doi = {10.1302/0301-620X.63B1.7204473},
url = {https://doi.org/10.1302/0301-620X.63B1.7204473}
}