When citing in the main text of your work the surnames of both should be given:-
When citing in the main text of your work the surname of the first author only should be given, followed by et al.:
Then all authors’ names should be noted in the reference list at the end.
et al. means 'and others'
Write an organisations' name in full, and, include the abbreviation or acronym in brackets. Thereafter in your work, when you refer to the organisation, you can use the abbreviation.
e.g. According to the Higher Education Policy Institute (HEPI)…
In the reference list always write the organisations' name in full.