Reference equations using letters and numbers in Microsoft Word 2010

Question

I want to have equations numbered like (1.1a) (1.1b).

It's like this question in TEX but I want to do it in Microsoft Word 2010.

I already know how to number equations using this great question How to add equation numbers to Microsoft Word 2010 equations, but I don't know how to add numbers and letters.

Answer 1

My solution in Numbering equations based on chapter numbers in MS-Word should give a start.

This time you create two labels:

{ STYLEREF 1 \s }.{ SEQ eqn \* Arabic \s 1 \* MERGEFORMAT }{ SEQ eqABC \* alphabetic \r 1\* MERGEFORMAT }
{ STYLEREF 1 \s }.{ SEQ eqn \* Arabic \s 1 \* MERGEFORMAT }{ SEQ eqABC \* alphabetic \* MERGEFORMAT }

The first one always starts with "a" because of "\r 1". The second label is for counting further. Thus, behind the equation which should have the "a" you put the first label and behind each other you put the second.

To simplify the usage you add two AutoCorrect entries such as (EQ_S) and (EQ_E) for the two labels as described in the linked article.