Editing Isomorphism theorems (section)

=== Note on numbers and names ===
Below we present four theorems, labelled A, B, C and D. They are often numbered as "First isomorphism theorem", "Second..." and so on; however, there is no universal agreement on the numbering. Here we give some examples of the group isomorphism theorems in the literature. Notice that these theorems have analogs for rings and modules.

<!-- Do not expand this list indiscriminately. This is here just to show the lack of the established convention. -->
{| class="wikitable"
|+ Comparison of the names of the group isomorphism theorems
|-
! scope="col" | Comment
! scope="col" | Author
! scope="col" | Theorem A
! scope="col" | Theorem B
! scope="col" | Theorem C
|-
| rowspan=4 | No "third" theorem
! Jacobson<ref>Jacobson (2009), sec 1.10</ref>
| Fundamental theorem of homomorphisms
| (''Second isomorphism theorem'')
| "often called the first isomorphism theorem"
|-
! van der Waerden,<ref>van der Waerden, ''[[Moderne Algebra|Algebra]]'' (1994).</ref> Durbin{{refn| ''[the names are] essentially the same as [van der Waerden 1994]''<ref>Durbin (2009), sec. 54</ref>}}
| Fundamental theorem of homomorphisms
| First isomorphism theorem
| Second isomorphism theorem
|-
! Knapp<ref>Knapp (2016), sec IV 2</ref>
| (''No name'')
| Second isomorphism theorem
| First isomorphism theorem
|-
! Grillet<ref>Grillet (2007), sec. I 5</ref>
| Homomorphism theorem
| Second isomorphism theorem
| First isomorphism theorem
|-
| rowspan=4 | Three numbered theorems
! (''Other convention per Grillet'')
| First isomorphism theorem
| Third isomorphism theorem
| Second isomorphism theorem
|-
! Rotman<ref>Rotman (2003), sec. 2.6</ref>
| First isomorphism theorem
| Second isomorphism theorem
| Third isomorphism theorem
|-
! Fraleigh<ref>Fraleigh (2003), Chap. 14, 34</ref>
| Fundamental homomorphism theorem or first isomorphism theorem
| Second isomorphism theorem
| Third isomorphism theorem
|-
! Dummit & Foote<ref>{{Cite book|last=Dummit|first=David Steven|url=https://www.worldcat.org/oclc/52559229|title=Abstract algebra|date=2004|others=Richard M. Foote|isbn=0-471-43334-9|edition=Third|publisher=John Wiley and Sons, Inc.|location=Hoboken, NJ|pages=97–98|oclc=52559229}}</ref>
| First isomorphism theorem
| Second or Diamond isomorphism theorem
| Third isomorphism theorem
|-
| rowspan=2 | No numbering
! Milne<ref name="milne">Milne (2013), Chap. 1, sec. ''Theorems concerning homomorphisms''</ref>
| Homomorphism theorem
| Isomorphism theorem
| Correspondence theorem
|-
! Scott<ref>Scott (1964), secs 2.2 and 2.3</ref>
| Homomorphism theorem
| Isomorphism theorem
| Freshman theorem
|}
<!-- Do not expand this list indiscriminantly. This is here just to show the lack of the established convention. -->
It is less common to include the Theorem D, usually known as the ''[[lattice theorem]]'' or the ''correspondence theorem'', as one of isomorphism theorems, but when included, it is the last one.