I know that the answer to the question "Who did Jack White work with on his album?" is in "In 2014 artist Jack White sold 40,000 copies of his second solo release, Lazaretto, on vinyl. The sales of the record beat the largest sales in one week on vinyl since 1991. The sales record was previously held by Pearl Jam's, Vitalogy, which sold 34,000 copies in one week in 1994. In 2014, the sale of vinyl records was the only physical music medium with increasing sales with relation to the previous year. Sales of other mediums including individual digital tracks, digital albums and compact discs have fallen, the latter having the greatest drop-in-sales rate.". Can you tell me what it is?
A:
solo