{{Cite book| publisher = ined/CEPED| pages = 25–54| editors = Philippe Antoine, Eva Lelièvre, Groupe de Réflexion sur l’Approche Biographique (GRAB) (eds.)| last1 = Lelièvre| first1 = Eva| last2 = Roubaud| first2 = François| last3 = Tichit| first3 = Christine| last4 = Vivier| first4 = Géraldine| title = Fuzzy states and complex trajectories. Observation, modelization and interpretation of life histories| chapter = Factual Data and Perceptions: Fuzziness in observation and analysis| location = Paris| series = Méthodes et Savoirs| date = 2009}}