In some academic disciplines the distinction between a secondary and tertiary source is relative, but in historiography it is absolute. In the UNISIST model, a secondary source is a bibliography, whereas a tertiary source is a synthesis of primary sources.
English Name for Vasambu is Sweet Flag. It is a semi-aquatic perennial herb whose scientific name is Acorus Calamus. In HIndi, it is called Bach. It is also called Bach in Bengali. would like to know the hindi/eng name for taml herb vasambu.
Etymology[edit] AsbÄb is the plural of the Arabic word sabab, which means cause, reason, or occasion, and nuzÅ«l is the verbal noun of the verb root nzl, literally meaning to descend or to send down, and thus (metaphorically) to reveal, referring Allah sending down a revelation to his prophets.