Function RechercheNom(dat As Range, mot As String) As String
If Not IsDate(dat) Then Exit Function
Dim c As Range, lig&, cc As Range
With Sheets("Base de donnée")
For Each c In .UsedRange
If IsDate(c) Then
If c = dat Then
lig = c.Row
For Each cc In Intersect(.UsedRange, c.EntireColumn)
If cc.Row > lig Then 'sous ia date
If cc = mot Then RechercheNom = .Cells(cc.Row, 2): Exit Function
End If
Next cc
End If
End If
Next c
End With
End Function