Take context from the input text and decide on the accurate relationship between 'Lafarge' and 'cement' from the options provided.
Options: position held, product/material produced, founded by, platform

The firm has just named Wolfgang Reitzle as an advisory partner the very same Wolfgang Reitzle who hired Perella Weinberg as an adviser to steer the rocky $44bn (£28.2bn) merger between his Swiss cement firm Holcim and its French rival Lafarge (EUREX: 504482.EX - news ) .
product/material produced