How to Identify Antique Secretary Desk

Okay, I need to help the user with their query on how to identify an antique secretary desk. Let me start by understanding what exactly they're asking for. They want a comprehensive article covering several aspects, from definitions to market trends. First, I’ll check the search results provided. The user has given 16 sources, so I need to go through them to find relevant information. Let me start by skimming each source to see which ones discuss identification, history, types, valuation factors, authenticity, market trends, buying/selling, and maintenance.