All of these (including (''M,R'') systems) found their original inspiration in Erwin Schrödinger's book ''What is Life?''<ref>{{cite book| last1 = Schrödinger| first1 = Erwin|title = What is Life? |publisher = Cambridge University Press|date = 1944}}</ref> but at first they appear to have little in common with one another, largely because the authors did not communicate with one another, and none of them made any reference in their principal publications to any of the other theories. Nonetheless, there are more similarities than may be obvious at first sight, for example between Gánti and Rosen.<ref>{{cite journal | doi= 10.1016/j.jtbi.2015.05.015|title = Tibor Gánti and Robert Rosen: contrasting approaches to the same problem|last1 =Cornish-Bowden | first1 =A.|journal= J. Theor. Biol. |volume = 381|pages = 6–10|date=2015}}</ref> Until recently<ref>{{cite journal | doi= 10.1016/j.jtbi.2011.06.033 |title= From ''L’Homme Machine'' to metabolic closure: steps towards understanding life|last1 = Letelier|first1 = J C|last2=Cárdenas |first2 =M L|last3=Cornish-Bowden|first3 =A |journal=J. Theor. Biol. | date = 2011 | volume= 286|issue= 1 | pages= 100–113}}</ref><ref>{{cite journal | doi= 10.1016/j.biosystems.2014.03.002| title=Time rescaling and pattern formation in biological evolution| journal =BioSystems|volume=123 |pages= 19–26|date= 2014|last=Igamberdiev|first=A.U.}}</ref><ref>{{cite journal | doi= 10.1016/j.biosystems.2019.104063 | All of these (including (''M,R'') systems) found their original inspiration in Erwin Schrödinger's book ''What is Life?''<ref>{{cite book| last1 = Schrödinger| first1 = Erwin|title = What is Life? |publisher = Cambridge University Press|date = 1944}}</ref> but at first they appear to have little in common with one another, largely because the authors did not communicate with one another, and none of them made any reference in their principal publications to any of the other theories. Nonetheless, there are more similarities than may be obvious at first sight, for example between Gánti and Rosen.<ref>{{cite journal | doi= 10.1016/j.jtbi.2015.05.015|title = Tibor Gánti and Robert Rosen: contrasting approaches to the same problem|last1 =Cornish-Bowden | first1 =A.|journal= J. Theor. Biol. |volume = 381|pages = 6–10|date=2015}}</ref> Until recently<ref>{{cite journal | doi= 10.1016/j.jtbi.2011.06.033 |title= From ''L’Homme Machine'' to metabolic closure: steps towards understanding life|last1 = Letelier|first1 = J C|last2=Cárdenas |first2 =M L|last3=Cornish-Bowden|first3 =A |journal=J. Theor. Biol. | date = 2011 | volume= 286|issue= 1 | pages= 100–113}}</ref><ref>{{cite journal | doi= 10.1016/j.biosystems.2014.03.002| title=Time rescaling and pattern formation in biological evolution| journal =BioSystems|volume=123 |pages= 19–26|date= 2014|last=Igamberdiev|first=A.U.}}</ref><ref>{{cite journal | doi= 10.1016/j.biosystems.2019.104063 |