Cost of health systems strengthening for small and sick newborn care in four sub-Saharan African countries implemented with NEST360: incremental cost analyses. - Tarus A; Kumar MB; Penzias RE; Kamuyu R; Cross JH; Sipalo M; Gicheha E; Bohne CA; Okello G; Macharia WM; Paul C; Salim N; et al. (The Lancet. Global health, 2026)