Recently our understanding of Cretaceous birds is being expanded by exceptional discoveries of small enantiornithine birds trapped in Cenomanian aged amber from Myanmar. These discoveries include two nearly complete individuals and one isolated hindlimb that represents a new species, Elektorornis chenguangi. So far six skeletal specimens have been uncovered, all of which have been described by me.
https://www.nationalgeographic.com/news/2017/06/baby-bird-dinosaur-burmese-amber-fossil/
https://www.cnn.com/2019/07/11/world/ancient-bird-foot-lizard-microraptor-scn/index.html
https://www.cnn.com/2019/07/11/world/ancient-bird-foot-lizard-microraptor-scn/index.html
https://www.sciencemag.org/news/2017/06/baby-bird-trapped-amber-lived-alongside-dinosaurs
https://www.newsweek.com/99-million-year-old-bird-lived-dinosaurs-found-trapped-ancient-amber-829175
Link to articles:
https://www.nature.com/articles/ncomms12089
https://www.sciencedirect.com/science/article/abs/pii/S1342937X17300527
https://www.sciencedirect.com/science/article/pii/S2095927318300331
https://www.nature.com/articles/s41598-018-37427-4
https://www.sciencedirect.com/science/article/abs/pii/S0960982219306918