Please indicate what you mean by a reference solution.
They can be called a range or a block.
In a business letter, the salutation comes after the reference. Typically, the reference is included in the header or body of the letter, often as a reference line or subject line, and serves to indicate the purpose or context of the correspondence. The salutation follows, addressing the recipient directly, such as "Dear [Recipient's Name]."
The letters "Re" on correspondence stand for "regarding" or "in regard to." It is often used as a subject line to indicate the topic or purpose of the communication.
The term re usually is an abbreviation for the word regarding.
by providing an answer to the question, does it indicate the purpose of this web site ?
To indicate the temperature?
To indicate wealth and status
What is the purpose of a contract?
A basketball reference serves the purpose of comparing basketball statistics. It is useful as a database that can be used for looking up a variety of statistics.
tertiary standard
You need to specify in what sense it became 'official' and for what purpose.