Spanish textbooks update frequently. The version floating around on VK might be the 2013 edition (often labeled "Nueva Edición"). The current standard is the "Edición Actualizada" (2020+). If you use an old PDF, the page numbers, audio tracks, and even the vocabulary might not match your classroom syllabus or modern usage.
Complete CD tracks (often in .rar or .7z format) corresponding to the listening exercises in the textbook. Supplementary Files: Some communities post additional PDFs for the Nueva edición (New Edition) or the updated Aula Internacional Plus Typical Unit Structure aula internacional 1 vk