Recommended by Elsevier

http://webshop.elsevier.com/

edanz (recommended by Springer)

https://www.edanzediting.com/?utm_source=springer&utm_medium=partner_link&utm_content=recommendation_page&utm_campaign=springer_general

Nature Publishing Group Language Editing (recommended by Springer)

https://languageediting.nature.com/?utm_source=springerlinkauthors&utm_medium=referral&utm_campaign=OUTSPRINGERMSGUIDELINES

Swift proof reading

http://www.swiftproofreading.org/index.php