In 1778 he becomes the assistant of the Riga chief architect J.P. Leicht .
In 1777 Haberland returned to Riga , passed his exam of master craftsmen and was admitted in the mason guild .
In 1778 Haberland becomes the assistant of the Riga chief architect J.P. Leicht .
In 1777 Haberland returned to Riga , passed his exam of master craftsmen and was admitted in the mason guild .