Simplify the following text for a Grade 12 native English-speaking person.
Original: Community rituals are usually based on traditional community celebrations found in folkloric collections by authors such as Marian McNeill , Kevin Danaher or John Gregorson Campbell .
Simplified: Celebratory , community rituals are usually based on community festivals as recorded in folklore collections by authors such as F. Marian McNeill , Kevin Danaher or John Gregorson Campbell .