Many chapters include problems curated from previous years' national-level competitive examinations. Critical Note on "Extra Quality" PDFs
As for accessing the PDF version of the book, I couldn't find any direct links to download it. However, I can suggest some possible sources: Many chapters include problems curated from previous years'
Websites like Library Genesis (LibGen), PDF Drive, or Academia.edu host user-uploaded files. However, "extra quality" is rare here. You will find mostly: or Academia.edu host user-uploaded files. However
Raisinghania, M.D. (Year of Publication). Advanced Differential Equations . New Delhi: S. Chand Publishing. [PDF – Extra Quality Scan] Many chapters include problems curated from previous years'