Perhaps you should try some spelling variations:
"et integral formulation" » "et lineal formulacion", "e integral formulation", "_ integral formulation", "la integral formulation"
"de integral formulation" » "de lineal formulacion", "e integral formulation", "de integrar formulation", "de integrales formulation"
"pat una formulacion" » "pat la formulacion", "pat de formulacion", "pat y formulacion", "part una formulacion", "past una formulacion"

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (("pat una formulacion") OR ((("et integral formulation") OR ("de integral formulation"))))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"pat una formulacion\") OR (((\"et integral formulation\") OR (\"de integral formulation\"))))".
• Removing quotes may allow a broader search: (( pat una formulacion ) OR ((( et integral formulation ) OR ( de integral formulation )))).
• Adding a wildcard symbol may retrieve word variants: (("pat una formulacion") OR ((("et integral formulation") OR ("de integral formulation"))))*.