Font used in Stewart's Calculus

I will use a style of this type in pdfLaTeX (too long for a complete comment).

documentclass[a4paper,12pt]{article}
usepackage[T1]{fontenc}
usepackage{amsmath,amssymb}
usepackage{mathptmx}
makeatletter
defupintkern@{mkern-7mumathchoice{mkern-3.5mu}{}{}{}}
defupintdots@{mathchoice{mkern-4mu@cdotsmkern-4mu}%
 {{cdotp}mkern1.5mu{cdotp}mkern1.5mu{cdotp}}%
 {{cdotp}mkern1mu{cdotp}mkern1mu{cdotp}}%
 {{cdotp}mkern1mu{cdotp}mkern1mu{cdotp}}}
newcommand{upiint}{DOTSIprotectUpMultiIntegral{2}}
newcommand{upiiint}{DOTSIprotectUpMultiIntegral{3}}
newcommand{upiiiint}{DOTSIprotectUpMultiIntegral{4}}
newcommand{upidotsint}{DOTSIprotectUpMultiIntegral{0}}
newcommand{UpMultiIntegral}[1]{%
  edefints@c{noexpandupintop
    ifnum#1=z@noexpandupintdots@elsenoexpandupintkern@fi
    ifnum#1>tw@noexpandupintopnoexpandupintkern@fi
    ifnum#1>thr@@noexpandupintopnoexpandupintkern@fi
    noexpandupintop
    noexpandilimits@
  }
  futurelet@let@tokenints@a
}
makeatother

DeclareFontFamily{OMX}{mdbch}{}
DeclareFontShape{OMX}{mdbch}{m}{n}{ <->s * [1]  mdbchr7v }{}%old 0.8
DeclareFontShape{OMX}{mdbch}{b}{n}{ <->s * [1]  mdbchb7v }{}%old 0.8
DeclareFontShape{OMX}{mdbch}{bx}{n}{<->ssub * mdbch/b/n}{}

DeclareSymbolFont{uplargesymbols}{OMX}{mdbch}{m}{n}
SetSymbolFont{uplargesymbols}{bold}{OMX}{mdbch}{b}{n}
DeclareMathSymbol{upintop}{mathop}{uplargesymbols}{82}
DeclareMathSymbol{upointop}{mathop}{uplargesymbols}{"48}

DeclareFontEncoding{MDB}{}{}
DeclareFontFamily{MDB}{mdbch}{}
DeclareFontShape{MDB}{mdbch}{m}{n}{ <->s * [0.8]  mdbchrmb }{}
DeclareFontShape{MDB}{mdbch}{b}{n}{ <->s * [0.8]  mdbchbmb }{}
DeclareFontShape{MDB}{mdbch}{bx}{n}{<->ssub * mdbch/b/n}{}
DeclareFontSubstitution{MDB}{cmr}{m}{n}
DeclareSymbolFont{mathdesignB}{MDB}{mdbch}{m}{n}%
SetSymbolFont{mathdesignB}{bold}{MDB}{mdbch}{b}{n}%
DeclareMathSymbol{upintclockwise}{mathop}{mathdesignB}{128}
DeclareMathSymbol{upointclockwise}{mathop}{mathdesignB}{130}
DeclareMathSymbol{upointctrclockwise}{mathop}{mathdesignB}{132}
DeclareMathSymbol{upoiint}{mathop}{mathdesignB}{134}
DeclareMathSymbol{upoiiint}{mathop}{mathdesignB}{136}
makeatletter
newcommand{upint}{DOTSIupintopilimits@}
newcommand{upoint}{DOTSIupointopilimits@}
makeatother


begin{document}
[ upiintlimits_S sum^{n}_{i=1}{}partial ]
end{document}