Are you saying you have something like this:

1 CENS
2 DATE 02 APR 1871
2 SOUR @Snn@
3 PAGE this is the citation
2 PLAC Somewhere in Canada

0 @Snn@ SOUR
1 TITL Canada Census 1891
1 URL google.com
1 URL http://www.bac-lac.gc.ca/eng/census/1891/Pages/…

Are you using repositories? They are the place (or web site) where the source is stored, or at least the version of the source you accessed.

I would say that “Library and Archives Canada” is really the source, with a URL of http://www.bac-lac.gc.ca, and that “http://www.bac-lac.gc.ca/eng/census/1891/Pages/… ” is the citation attached to the source for this event. So the full ‘set’ would then become:

1 CENS
2 DATE 02 APR 1891
2 PLAC Somewhere in Canada
2 SOUR @Snn@
3 PAGE http://www.bac-lac.gc.ca/eng/census/1891/Pages/…

0 @Snn@ SOUR
1 TITLE Library and Archives Canada – Canada 1911 Fifth General Census
1 REPO @Rnnn@

0 @Rnnn@ REPO
1 NAME What ever name you associate with the website at bac-lac.gc.ca
1 URL http://www.bac-lac.gc.ca

As for combining three possible sites where the same data can be found the short answer is no. Besides, if you ever feel that something has to be done via raw GEDCOM edit, then you can be almost certain you are doing it wrong!

Three different sites where a piece of data can be found = three different sources for that data, so record them as such if you feel it is worthwhile. But if they are all identical (i.e. using the same transcription of the same original source pages) then what is the purpose? If they are different transcriptions, then by all means record them, but as different sources, with different results.

Or keep it really simple. Record the source as the ‘best’ source, and add text to the citation, or an additional note saying “The same information is also available at http://www.google.com ” or whatever.

There is an old adage about ‘good’ genealogy that says something like “no fact can be taken as proven until you have three pieces of evidence (sources) to confirm it”. That means three distinct and separate sources, not the same source from three different places 🙂 The latter doesn’t really achieve anything from an evidence point of view. Only useful as short additional information, which is the definition of a NOTE.

I always find questions about sources etc easiest to follow if you always go back the basic old-fasioned terminolgy. The terms may have changed in this digital age, but the principles are identical:

REPOsitory – the place where you can go to find the information quoted. (A building, or a web site?)

SOURce – the book that you looked in for the information used to inform a number of facts or events.

Citation (PAGE) – the place in the book, possible even the paragraph that provided the specific information for THIS event.