42.2 - Aircraft engine repairs ‑ associated companies 43.2 - Aircraft engine repairs ‑ outside 43.7 - Aircraft interchange charges ‑ outside 42.7 - Aircraft interchange charges ‑ associated companies 42.1 - Airframe repairs ‑ associated companies 43.1 - Airframe repairs ‑ outside 37 - Air‑ground radio service 41 - Appraisal fees 41 - Architect fees 40 - Attorney fees and expenses 41 - Audit fees 43.9 - Bank service charges 60 - Billboards 39 - Commission ‑ traffic, Group I carriers 39.1 - Commission ‑ passenger traffic, Group II and III carriers 39.2 - Commission ‑ cargo traffic, Group II and III carriers 41 - Consultants 43.9 - Credit and billing services 60 - Direct mail advertising 60 - Directories, guides and programs 60 - Displays 37 - Equipment installation charges 41 - Engineering services 42.6 - Flight equipment repairs ‑ associated companies, Group I carriers 43.6 - Fight equipment repairs ‑ outside, Group I carriers 43.9 - Fuel Servicing (in-to-plane fees) 43.9 - Housekeeping and support services 42.8 - Interchange service charges (general) associated companies 43.8 - Interchange service charges (general) outside 37 - Intercommunication equipment 41 - Laboratory services 40 - Law books 40 - Legal fees and expenses 40 - Legal forms and supplies 40 - Litigation costs 60 - Magazines and trade publications 41 - Market and traffic surveys 41 - Medical 37 - Navigation facility user charges 60 - Newspaper advertising 42.3 - Other flight equipment repairs ‑ associated companies 43.3 - Other flight equipment repairs ‑ outside 42.9 - Other services ‑ associated companies 43.9 - Other services ‑ ou‑tside companies 60 - Posters and signs ‑ advertising 60 - Radio ‑ advertising