Given the different DOIs it might be tricky but how about the approach from

https://explore.researchgate.net/display/support/Reviewing%2C+featuring%2C+and+editing+your+research

(scroll to Why are there duplicate research items on my profile?)?

Thank you, Artur.

It seems no possibility of merging two items with different DOIs. It is the publisher, APA, who is to be blamed. They assigned a new DOI to my paper with a DOI.

Dear Kazuo Mori Normally you can merge two papers, see for example here on RG: https://www.researchgate.net/post/Merging-two-same-papers-in-a-one-paper Indeed, the new owner assigned a new DOI:

https://psycnet.apa.org/doiLanding?doi=10.1037%2Fh0101833

if I enter your paper through Elsevier:

https://www.sciencedirect.com/science/article/abs/pii/S2211368118301062 and I click on the (obsolete/original DOI link) I get redirected to the new owner.

Personally, I would try to merge them, see the section "Why are there duplicate research items on my profile?" in the help page https://explore.researchgate.net/display/support/Reviewing%2C+featuring%2C+and+editing+your+research and use the original DOI.

Best regards.

PS. I agree with you something went wrong here and the new owner is to blame. Fortunately, I had a proper experience with one of my papers:

My paper with DOI 10.2478/s11658-010-0036-y was published by Versita:

Article The prediction of novel multiple lipid-binding regions in pr...

and (at the same time?) used to be part of/published by Springer:

https://link.springer.com/article/10.2478/s11658-010-0036-y

then the journal behind it was transferred to de Gruyter:

https://www.degruyter.com/document/doi/10.2478/s11658-010-0036-y/html

and is nowadays part of the BMC portfolio (which is part of Springer):

https://cmbl.biomedcentral.com/articles/10.2478/s11658-010-0036-y ...and all with the same DOI.

I recommend to delete the DOIs in both entries and to make the entries identical. Then wait a few days until the two entries will have been merged automatically. Finally, add one of the DOIs.

Thank you, Wolfgang;

I'll try your advice.

Dear Kazuo Mori I am afraid that the 'passive' approach will not work. But now you removed the DOI's in both entries I think you can merge them yourself.

Best regards.

Thank you, again. I'll try the active approach as you advised.

Best regards.