@incollection{Richards13,
author = {Richard A. Richards},
title = {The Species Problem: A Conceptual Problem?},
booktitle = {The Species Problem},
publisher = {IntechOpen},
address = {Rijeka},
year = {2013},
editor = {Igor Ya. Pavlinov},
chapter = {2},
doi = {10.5772/54134},
url = {https://doi.org/10.5772/54134}
}