"duly obtained" is correct and usable in written English.
You can use it when something has been correctly and officially acquired or completed. For example, "The legal documents were duly obtained for the property transfer."
Being a good citizen, I duly obtained a dog license from the city, leashed her when we roamed the streets, and made sure she left no unsightly residues.
A medal was duly obtained and was subsequently placed in the Mint's collection.
He suggested that mill owners could be protected by a suitable clause in the bill, and such a clause was duly obtained by Robert Peel.
A written informed consent from each of the participants or legal representatives was duly obtained.
Ethical clearance was duly obtained from the Ethics and Research committee of the hospital.
Thorough physical examination was conducted and complete blood count, ESR, IgM rheumatoid factor, and C reactive protein values were obtained and duly taken into account.
Finally, the effectiveness of the proposed method is investigated by applying it on the 54-bus distribution network and the obtained results are duly drawn and discussed.
This discussion shows that procedures 1 and 2 involve variations typical of different approximations and calculation methods and that such differences are almost negligible with respect to the variations obtained when taking duly into account crosswind and torsional accelerations.
Participants' consent was obtained after being duly informed on the purpose of the study and the interview process, while it was explicitly stated that participation was entirely voluntary and that their anonymity would be ensured.
Research participants will be duly informed and consent will be obtained in writing prior to participation.
