{{cite journal |last=The Data Nerd |title=Panel structure: 219 observations across 55 unique startups |journal=SSRN Electronic Journal |year=2026 |doi=10.2139/ssrn.6606558 |url=https://signals.gitdealflow.com/research/panel-structure-219-observations-55-startups |publisher=VC Deal Flow Signal (GitDealFlow) |orcid=0009-0002-2222-4112 |at=§4.1 Structure}}