@article{article,
title = {Analysis of trace elements by proton induced x ray emission in serum of patients with liver cancer and normal subjects},
author = {Et Al},
year = {1985},
journal = {Zhonghua Zhongliu Zazhi},
volume = {7},
number = {6},
pages = {411-413},
howpublished = "\url{https://eurekamag.com/research/004/744/004744641.php}"
}