Contributors who are not authors also need to be thanked. List these people in your Acknowledgements section, along with any funding agencies and grant numbers. Specify what contribution each person made towards the final work.
Your Acknowledgements should include people who:
Only people who have had major and important involvement in the work must be listed as authors. Do not “gift” authorship to someone who has not made an important contribution. This is known as “honorary authorship” and is highly unethical. Instead, name these lesser contributors in your Acknowledgements section and specify their contribution.
On the other hand, do not try to move an author’s name down to the Acknowledgements section to avoid declaring a potential conflict of interest. This is called “ghost authorship” and is also very unethical. Always be honest about potential conflicts of interest. Everyone who meets authorship criteria should share responsibility for the paper.
You also need written permission from anyone you name in the Acknowledgments section. Be sure to do this before you submit your manuscript.