What is the grammatically correct way of attributing possession to the noun phrase "her and others"?

Solution 1:

I know Fowler was writing a hundred years ago but, as there are still no generally-agreed rules about two possessives in a row, maybe his words are still helpful.

From The King's English:

"I am not sure yours and my efforts would suffice separately; but yours and mine together cannot possibly fail."

The first yours is quite wrong; it should be your.

And

"You altered the succession to theirs, as well as to your own crown." — Burke.

We might possibly tolerate to their as well as to your own; or we might write to their crown as well as to your own.

From A Dictionary of Modern English Usage:

A mistake is often made when two or more possessives are to be referred to a single noun that follows. The correct forms are: your and our and his efforts (not yours and ours); either my or your informant must have lied (not mine); her and his mutual dislike (not hers).
There is no doubt a natural temptation to substitute the wrong word; the simple possessive seems to pine at separation from its property. The true remedy is a change of order: your efforts and ours and his; my informant or yours; our help without yours. It is not always available, however; her and his mutual dislike must be left as it is.