translate English to French: Each section (4.2.1 - 4.2.5) is cross-referenced to respective sections (4.1.1 - 4.1.5) under Drug Substance.
Chaque section (4.2.1-4.2.5) est renvoyée aux sections pertinentes (4.1.1-4.1.5) sous "Substance médicamenteuse".