NCBI EUtils: identifying projects with both NGS and Sanger sequencing

Question

[sovrappensiero]

I'd like to write a short script to identify BioProjects in NCBI where the researchers have done two forms of sequencing - say, NGS and confirmatory Sanger sequencing. These don't seem to show up under the index list for "Project Data Type." I looked through the XML output of some of the BioProjects I have, and read this NCBI book on BioProjects, but nothing jumped out at me as an obvious way to approach this problem. Is this possible? If so, where can I find this info encoded? (Or if not for BioProject, is it possible to ID these through some other database?) I just need a head start, and I can handle the rest... Thanks in advance for your time!