Obtaining a death record in Amsterdam for Mario Lenassi who died on 25 June 1929 is a bit difficult.
The index books are not on line.
There are 2 books with death records for the period mid May to mid July for the central city.
See on http://www.genver.nl/nh/0363o.htm
8193170 Overlijden 1927-1929 dl 9-12 en dl 1-12 en dl 1-14 geïndexeerd op jaar. Click there on geïndexeerd op jaar.
This leads you to http://www.genver.nl/nh/ndx0363o.htm#8193170
where you can see the lines
1929 2124/2224 register 7 oneven akten 3583-4775, 10 mei - 15 jul
1929 2225/2326 register 8 even akten 3584-4776, 10 mei - 16 jul
By clicking on the numbers you get to records starting om 10 May and ending on 15 or 16 July.
I did a quick search, but did not see him.. Maybe I overlooked him.
There were also registration offices in suburbs,but these are not on familysearch.
I think that I wiill need to visit the city archive to look in the 1929 index to see where his death record is registered.
Unfortunately a dutch death record gives his death date and not where he is buried, For that you need a copy of the "verlof tot begraven" or burial permit.
I do not know of copies of those are kept. The originals go to the burialplace and might be kept there.
for possibilities in Amsterdanm
The name Mario Lenassi does not sound dutch. I see on http://kranten.kb.nl/view/article/id/ddd%3A010531205%3Ampeg2...
that he is an person of italian nationality so he mght have been buried in Italy.